POJ经典题目分类

poj搜索题总结——初期篇简单搜索(1)深度优先搜索(poj2488,poj3009,poj1321)(2)广度优先搜索(poj3278,poj1426,poj3126,poj3087.poj3414,poj2251,poj3083)(3)简单搜索技巧和剪枝(poj2531,poj1416,poj2676,1129)看到这些题是不是很眼熟。

没错，这就是某位大牛推荐初期要做的题。

而这文章就是为这些题加上解题报告以及一些总结。

深度优先搜索poj2488：A Knight's Journey如果没有按字典序输出这个要求的话，就是简单的DFS，但是加上的话，就是麻烦题。

这就要求求出全部的走法或在行走时，按照某种顺序走。

从时间上来说，当然是选择第二种了。

若存在可行路线，则每个格子必然都走过。

所以从A1开始，按照某种顺序走，若有解，则为所求，若无，则无解。

//W A了N次,才发现是倒在字典序的手下//虽然题目没说，但是这道题最后一组数据后是没有空行的...否则会PE...//若存在可行路线，则每个格子都走过。

所以从（0，0）开始即可，不需要遍历每一个起始点//注意行走的方法（即MOV数组元素的排列），可以在找到可行解时，就使得其字典序最小#include<iostream>#include<string>#include<fstream>using namespace std;bool flag;string answer[30];int chess[30][30];//这个的设置一定要与下面的转换相对应，之前就是不对应，错了N次int mov[8][2]={{-1,-2},{1,-2},{-2,-1},{2,-1},{-2,1},{2,1},{-1,2},{1,2}};string GetPosition(int x,int y) { //将X，Y坐标转换成题目要求的形式string stmp;stmp+=(char)(y+'A'); //由于先出现的是Y坐标（如B3），所以MOV数组中的Y 应从-2到2的顺序变化stmp+=(char)(x+'1');return stmp;}void SaveIt(int p,int q) { //保存下答案answer[chess[i][j]]=GetPosition(i,j);}}}void dfs(int p,int q,int num,int x,int y) {if( num==p*q ) {flag=true;SaveIt(p,q);return;}int xx,yy;for(int i=0;i<8;++i) {if( flag ) return ;xx=x+mov[i][0];yy=y+mov[i][1];if( (xx>=0 && xx<p) && (yy>=0 && yy<q) && chess[xx][yy]==0 ) {chess[xx][yy]=num+1;dfs(p,q,num+1,xx,yy);chess[xx][yy]=0;}}}int main() {ifstream cin("test.in");int cases,count(1),p,q,i;cin>>cases;while( cases-- ) {cin>>p>>q;flag=false;memset(chess,0,sizeof(chess));chess[0][0]=1;dfs(p,q,1,0,0);//outputcout<<"Scenario #"<<count++<<":"<<endl;if( flag ) {for(i=1;i<=p*q;++i) cout<<answer[i];cout<<endl;}}return 0;}poj1321：棋盘问题这题是简单的DFS，但题目有个地方说得不是很清楚，就是以“#”为标志的位置才能放棋子。

POJ图论分类2009-07-28 23:13POJ 2449 Remmarguts' Date(中等)/JudgeOnline/problem?id=2449题意：经典问题：K短路解法：dijkstra+A*(rec)，方法很多相关：/JudgeOnline/showcontest?contest_id=1144该题亦放在搜索推荐题中POJ 3013 - Big Christmas Tree(基础)/JudgeOnline/problem?id=3013题意：最简单最短路，但此题要过，需要较好的程序速度和，还要注意精度解法：DijkstraPOJ 3463 - Sightseeing(中等)/JudgeOnline/problem?id=3463题意：最短路和比最短路大1的路的数量解法：需要真正理解dijkstraPOJ 3613 - Cow Relays(较难)/JudgeOnline/problem?id=3613题意：求经过N条边的最短路解法：floyd + 倍增，贪心POJ 3621 - Sightseeing Cows(中等)/JudgeOnline/problem?id=3621题意：求一个环路，欢乐值/ 总路径最大解法：参数搜索+ 最短路(ms 原始的bellman tle, 用spfa才过)POJ 3635 - full tank?(中等)/JudgeOnline/problem?id=3635题意：最短路变形解法：广搜相关：/hnu_reason/blog/item/086e3dccfc8cb21600e9286b.html生成树问题基本的生成树就不放上来了POJ 1639 - Picnic Planning(较难)/JudgeOnline/problem?id=1639题意：顶点度数有限制的最小生成树解法：贪心+ prim/kruskalPOJ 1679 - The Unique MST(基础)/JudgeOnline/problem?id=1679 题意：判断MST是否唯一解法：prim就行，不过还是易错的题POJ 2728 - Desert King(中等)/JudgeOnline/problem?id=2728 题意：所谓最优比率生成树解法：参数搜索+ primPOJ 3164 - Command Network(难)/JudgeOnline/problem?id=3164 题意：最小树形图解法：刘朱算法，这个考到的可能性比较小吧？POJ 3522 - Slim Span(基础)/JudgeOnline/problem?id=3522 题意：求一颗生成树，让最大边最小边差值最小解法：kruskal活用连通性，度数，拓扑问题此类问题主要牵扯到DFS，缩点等技巧POJ 1236 - Network of Schools(基础)/JudgeOnline/problem?id=1236 题意：问添加多少边可成为完全连通图解法：缩点，看度数POJ 1659 - Frogs' Neighborhood(基础)/JudgeOnline/problem?id=1659 题意：根据度序列构造图解法：贪心，详细证明参见havel定理POJ 2553 - The Bottom of a Graph(基础)/JudgeOnline/problem?id=2553 POJ 2186 - Popular Cows(基础)/JudgeOnline/problem?id=2186 题意：强连通分量缩点图出度为0的点POJ 2762 - Going from u to v or from v to u?(中等) /JudgeOnline/problem?id=2762 题意：单向连通图判定解法：缩点+ dp找最长链POJ 2914 - Minimum Cut(难)/JudgeOnline/problem?id=2914题意：无向图最小割解法：Stoer-Wagner算法，用网络流加枚举判定会挂POJ 2942 - Knights of the Round Table(难)/JudgeOnline/problem?id=2942题意：求双联通分量(或称块)中是否含奇圈解法：求出双连通分量后做黑白染色进行二分图图判定相关：/zfy0701/blog/item/57ada7ed104ce9d2b31cb104.html POJ 3177 - Redundant Paths(中等)/JudgeOnline/problem?id=3177POJ 3352 - Road Construction(中等)/JudgeOnline/problem?id=3352题意：添加多少条边可成为双向连通图解法：把割边分开的不同分量缩点构树，看入度建议对比下1236，有向图添加多少条边变成强连通图POJ 3249 - Test for Job(基础)/JudgeOnline/problem?id=3249解法：bfs / dfs + dpPOJ 3592 - Instantaneous Transference(基础)/JudgeOnline/problem?id=3592解法：缩点，最长路，少人做的水题，注意细节POJ 3687 - Labeling Balls(中等)/JudgeOnline/problem?id=3687解法：拓扑排序POJ 3694 - Network(中等)/JudgeOnline/problem?id=3694解法：双连通分量+并查集2-SAT问题此类问题理解合取式的含义就不难POJ 2723 - Get Luffy Out(中等)/JudgeOnline/problem?id=2723POJ 2749 - Building roads(较难)/JudgeOnline/problem?id=2749解法：二分+ 2-SAT判定POJ 3207 - Ikki's Story IV - Panda's Trick(基础)/JudgeOnline/problem?id=3207解法：简单的2-sat，不过其他方法更快POJ 3648- Wedding(中等)/JudgeOnline/problem?id=3648解法：用2-sat做会比较有意思，但是暴搜照样0msPOJ 3678 - Katu Puzzle(基础)/JudgeOnline/problem?id=3678解法：直接按合取式构图验证就行了POJ 3683 - Priest John's Busiest Day(中等)/JudgeOnline/problem?id=3683解法：n^2枚举点之间的相容性构图，求解2-SAT最大流问题变形很多，最小割最大流定理的理解是关键POJ 1149 - PIGS(较难)/JudgeOnline/problem?id=1149绝对经典的构图题POJ 1273 - Drainage Ditches(基础)/JudgeOnline/problem?id=1273最大流入门POJ 1459 - Power Network(基础)/JudgeOnline/problem?id=1459基本构图POJ 1637 - Sightseeing tour(Crazy)/JudgeOnline/problem?id=1637题意：求混合图的欧拉迹是否存在解法：无向边任意定向，构图，详建黑书P324POJ 1815 - Friendship(中等)/JudgeOnline/problem?id=1815题意：求最小点割解法：拆点转换为边割相关：/zfy0701/blog/item/a521f230b06dea9fa9018e0e.html POJ 1966 - Cable TV Network(中等)/JudgeOnline/problem?id=1966题意：去掉多少点让图不连通解法：任定一源点，枚举汇点求点割集(转换到求边割)，求其中最小的点割POJ 2112 - Optimal Milking(基础)/JudgeOnline/problem?id=2112二分枚举，最大流POJ 2391 - Ombrophobic Bovines(中等)/JudgeOnline/problem?id=2391题意：floyd, 拆点，二分枚举相关：/zfy0701/blog/item/3e0006c4f73f0eaf8226acff.htmlPOJ 2396 - Budget(中等)/JudgeOnline/problem?id=2396题意：有源汇的上下界可行流解法：用矩阵-网络流模型构图，然后拆边相关：/zfy0701/blog/item/6449d82a64e15e3e5343c1ba.html ，最小割模型在竞赛中的应用POJ 2455 - Secret Milking Machine(基础)/JudgeOnline/problem?id=2455二分枚举，一般来说需要写对边容量的更新操作而不是每次全部重新构图POJ 2699 - The Maximum Number of Strong Kings(较难)/JudgeOnline/problem?id=2699解法：枚举人数+ 最大流(感谢xpcnq_71大牛的建图的提示)POJ 2987 - Firing(较难)/JudgeOnline/problem?id=2987题意：最大权闭包解法：先边权放大，第一问总量-最大流，第二问求最小割相关：/blog/cns!4D861A02A3382142!1109.entry?&_c02_o wner=1Profit(中等)/Problem_Show.asp?id=1352最大权闭包图的特殊情况ZOJ 2071 - Technology Trader 也是此类型，懒了没做/show_problem.php?pid=2071POJ 3084 - Panic Room(中等，好题)/JudgeOnline/problem?id=3084题意：略解法：根据最小割建模POJ 3155 - Hard Life(很挑战一题)/JudgeOnline/problem?id=3155题意：最大密度子图解法：参数搜索+ 最大权闭合图，A.V.Goldberg的论文(nb解法)最小割模型在信息学竞赛中的应用一文中也有讲POJ 3189 - Steady Cow Assignment(中等)/JudgeOnline/problem?id=3189题意：寻找最小的区间完成匹配解法：这题充分说明SAP的强大，纯暴力可过。

（一）：用的比较多的初期:一.基本算法:(1)枚举. (poj1753,poj2965)(2)贪心(poj1328,poj2109,poj2586)(3)递归和分治法.(4)递推.(5)构造法.(poj3295)(6)模拟法.(poj1068,poj2632,poj1573,poj2993,poj2996)二.图算法:(1)图的深度优先遍历和广度优先遍历.(2)最短路径算法(dijkstra,bellman-ford,floyd,heap+dijkstra)(poj1860,poj3259,poj1062,poj2253,poj1125,poj2240)(3)最小生成树算法(prim,kruskal)(poj1789,poj2485,poj1258,poj3026)(4)拓扑排序(poj1094)(5)二分图的最大匹配(匈牙利算法) (poj3041,poj3020)(6)最大流的增广路算法(KM算法). (poj1459,poj3436)三.数据结构.(1)串(poj1035,poj3080,poj1936)(2)排序(快排、归并排(与逆序数有关)、堆排) (poj2388,poj2299)(3)简单并查集的应用.(4)哈希表和二分查找等高效查找法(数的Hash,串的Hash)(poj3349,poj3274,POJ2151,poj1840,poj2002,poj2503)(5)哈夫曼树(poj3253)(6)堆(7)trie树(静态建树、动态建树) (poj2513)四.简单搜索(1)深度优先搜索(poj2488,poj3083,poj3009,poj1321,poj2251)(2)广度优先搜索(poj3278,poj1426,poj3126,poj3087.poj3414)(3)简单搜索技巧和剪枝(poj2531,poj1416,poj2676,1129)五.动态规划(1)背包问题. (poj1837,poj1276)(2)型如下表的简单DP(可参考lrj的书page149):1.E[j]=opt{D+w(i,j)} (poj3267,poj1836,poj1260,poj2533)2.E[i,j]=opt{D[i-1,j]+xi,D[i,j-1]+yj,D[i-1][j-1]+zij} (最长公共子序列) (poj3176,poj1080,poj1159)3.C[i,j]=w[i,j]+opt{C[i,k-1]+C[k,j]}.(最优二分检索树问题)六.数学(1)组合数学:1.加法原理和乘法原理.2.排列组合.3.递推关系.(POJ3252,poj1850,poj1019,poj1942)(2)数论.1.素数与整除问题2.进制位.3.同余模运算.(poj2635, poj3292,poj1845,poj2115)(3)计算方法.1.二分法求解单调函数相关知识.(poj3273,poj3258,poj1905,poj3122)七.计算几何学.(1)几何公式.(2)叉积和点积的运用(如线段相交的判定,点到线段的距离等). (poj2031,poj1039)(3)多边型的简单算法(求面积)和相关判定(点在多边型内,多边型是否相交) (poj1408,poj1584)(4)凸包. (poj2187,poj1113)中级:一.基本算法:(1)C++的标准模版库的应用. (poj3096,poj3007)(2)较为复杂的模拟题的训练(poj3393,poj1472,poj3371,poj1027,poj2706)二.图算法:(1)差分约束系统的建立和求解. (poj1201,poj2983)(2)最小费用最大流(poj2516,poj2516,poj2195)(3)双连通分量(poj2942)(4)强连通分支及其缩点.(poj2186)(5)图的割边和割点(poj3352)(6)最小割模型、网络流规约(poj3308, )三.数据结构.(1)线段树. (poj2528,poj2828,poj2777,poj2886,poj2750)(2)静态二叉检索树. (poj2482,poj2352)(3)树状树组(poj1195,poj3321)(4)RMQ. (poj3264,poj3368)(5)并查集的高级应用. (poj1703,2492)(6)KMP算法. (poj1961,poj2406)四.搜索(1)最优化剪枝和可行性剪枝(2)搜索的技巧和优化(poj3411,poj1724)(3)记忆化搜索(poj3373,poj1691)五.动态规划(1)较为复杂的动态规划(如动态规划解特别的施行商问题等)(poj1191,poj1054,poj3280,poj2029,poj2948,poj1925,poj3034)(2)记录状态的动态规划. (POJ3254,poj2411,poj1185)(3)树型动态规划(poj2057,poj1947,poj2486,poj3140)六.数学(1)组合数学:1.容斥原理.2.抽屉原理.3.置换群与Polya定理(poj1286,poj2409,poj3270,poj1026).4.递推关系和母函数.(2)数学.1.高斯消元法(poj2947,poj1487, poj2065,poj1166,poj1222)2.概率问题. (poj3071,poj3440)3.GCD、扩展的欧几里德(中国剩余定理) (poj3101)(3)计算方法.1.0/1分数规划. (poj2976)2.三分法求解单峰(单谷)的极值.3.矩阵法(poj3150,poj3422,poj3070)4.迭代逼近(poj3301)(4)随机化算法(poj3318,poj2454)(5)杂题.(poj1870,poj3296,poj3286,poj1095)七.计算几何学.(1)坐标离散化.(2)扫描线算法(例如求矩形的面积和周长并,常和线段树或堆一起使用).(poj1765,poj1177,poj1151,poj3277,poj2280,poj3004)(3)多边形的内核(半平面交)(poj3130,poj3335)(4)几何工具的综合应用.(poj1819,poj1066,poj2043,poj3227,poj2165,poj3429)高级:一.基本算法要求:(1)代码快速写成,精简但不失风格(poj2525,poj1684,poj1421,poj1048,poj2050,poj3306)(2)保证正确性和高效性. poj3434二.图算法:(1)度限制最小生成树和第K最短路. (poj1639)(2)最短路,最小生成树,二分图,最大流问题的相关理论(主要是模型建立和求解)(poj3155, poj2112,poj1966,poj3281,poj1087,poj2289,poj3216,poj2446(3)最优比率生成树. (poj2728)(4)最小树形图(poj3164)(5)次小生成树.(6)无向图、有向图的最小环三.数据结构.(1)trie图的建立和应用. (poj2778)(2)LCA和RMQ问题(LCA(最近公共祖先问题) 有离线算法(并查集+dfs) 和在线算法(RMQ+dfs)).(poj1330)(3)双端队列和它的应用(维护一个单调的队列,常常在动态规划中起到优化状态转移的目的). (poj2823)(4)左偏树(可合并堆).(5)后缀树(非常有用的数据结构,也是赛区考题的热点).(poj3415,poj3294)四.搜索(1)较麻烦的搜索题目训练(poj1069,poj3322,poj1475,poj1924,poj2049,poj3426)(2)广搜的状态优化:利用M进制数存储状态、转化为串用hash表判重、按位压缩存储状态、双向广搜、A*算法. (poj1768,poj1184,poj1872,poj1324,poj2046,poj1482)(3)深搜的优化:尽量用位运算、一定要加剪枝、函数参数尽可能少、层数不易过大、可以考虑双向搜索或者是轮换搜索、IDA*算法. (poj3131,poj2870,poj2286)五.动态规划(1)需要用数据结构优化的动态规划.(poj2754,poj3378,poj3017)(2)四边形不等式理论.(3)较难的状态DP(poj3133)六.数学(1)组合数学.1.MoBius反演(poj2888,poj2154)2.偏序关系理论.(2)博奕论.1.极大极小过程(poj3317,poj1085)2.Nim问题.七.计算几何学.(1)半平面求交(poj3384,poj2540)(2)可视图的建立(poj2966)(3)点集最小圆覆盖.(4)对踵点(poj2079)八.综合题.(poj3109,poj1478,poj1462,poj2729,poj2048,poj3336,poj3315,poj2148,poj1263)----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------以及补充Dp状态设计与方程总结1.不完全状态记录<1>青蛙过河问题<2>利用区间dp2.背包类问题<1> 0-1背包，经典问题<2>无限背包，经典问题<3>判定性背包问题<4>带附属关系的背包问题<5> + -1背包问题<6>双背包求最优值<7>构造三角形问题<8>带上下界限制的背包问题(012背包)3.线性的动态规划问题<1>积木游戏问题<2>决斗（判定性问题）<3>圆的最大多边形问题<4>统计单词个数问题<5>棋盘分割<6>日程安排问题<7>最小逼近问题(求出两数之比最接近某数/两数之和等于某数等等)<8>方块消除游戏(某区间可以连续消去求最大效益)<9>资源分配问题<10>数字三角形问题<11>漂亮的打印<12>邮局问题与构造答案<13>最高积木问题<14>两段连续和最大<15>2次幂和问题<16>N个数的最大M段子段和<17>交叉最大数问题4.判定性问题的dp(如判定整除、判定可达性等)<1>模K问题的dp<2>特殊的模K问题，求最大(最小)模K的数<3>变换数问题5.单调性优化的动态规划<1>1-SUM问题<2>2-SUM问题<3>序列划分问题(单调队列优化)6.剖分问题(多边形剖分/石子合并/圆的剖分/乘积最大)<1>凸多边形的三角剖分问题<2>乘积最大问题<3>多边形游戏(多边形边上是操作符,顶点有权值)<4>石子合并(N^3/N^2/NLogN各种优化)7.贪心的动态规划<1>最优装载问题<2>部分背包问题<3>乘船问题<4>贪心策略<5>双机调度问题Johnson算法8.状态dp<1>牛仔射击问题(博弈类)<2>哈密顿路径的状态dp<3>两支点天平平衡问题<4>一个有向图的最接近二部图9.树型dp<1>完美服务器问题(每个节点有3种状态)<2>小胖守皇宫问题<3>网络收费问题<4>树中漫游问题<5>树上的博弈<6>树的最大独立集问题<7>树的最大平衡值问题<8>构造树的最小环（二）：麻烦题：1697, 1712, 1713, 1720, 1729, 1765, 1772, 1858, 1872, 1960, 1963, 2050, 2122, 2162, 22 19, 2237,简单题目：1000, 1003, 1004, 1005, 1007, 1046, 1207, 1226, 1401, 1504, 1552, 1607, 1657, 1658, 16 74, 1799, 1862, 1906, 1922, 1929, 1931, 1969, 1976, 2000, 2005, 2017, 2027, 2070, 2101, 2105, 2109, 2116, 2136, 2160, 2190, 2232, 2234, 2275, 2301, 2350, 2363, 2389, 2393, 2 413, 2419,推荐：1063, 1064, 1131, 1140, 1715, 2163,杂题：1014, 1218, 1316, 1455, 1517, 1547, 1580, 1604, 1663, 1678, 1749, 1804, 2013, 2014, 20 56, 2059, 2100, 2188, 2189, 2218, 2229, 2249, 2290, 2302, 2304, 2309, 2313, 2316, 2323, 2326, 2368, 2369, 2371, 2402, 2405, 2407,推荐：1146, 1147, 1148, 1171, 1389, 1433, 1468, 1519, 1631, 1646, 1672, 1681, 1700, 1701, 17 05, 1728, 1735, 1736, 1752, 1754, 1755, 1769, 1781, 1787, 1796, 1797, 1833, 1844, 1882, 1933, 1941, 1978, 2128, 2166, 2328, 2383, 2420,高精度：1001, 1220, 1405, 1503,排序：1002, 1318, 1877, 1928, 1971, 1974, 1990, 2001, 2002, 2092, 2379, 2388, 2418,推荐：1423, 1694, 1723, 1727, 1763, 1788, 1828, 1838, 1840, 2201, 2376, 2377, 2380,搜索1676,1376,@3009,容易：1128, 1166, @1176, 1231, 1256, @1270, 1321, @1543, 1606, @1664, 1731, 1742, @174 5, 1847, 1915, 1950, 2038, 2157, 2182, 2183, 2381, 2386, 2426,不易：1024, 1054, 1117, 1167, 1708, 1746, 1775, 1878, 1903, 1966, 2046, 2197, 2349,推荐：1011, 1190, 1191, 1416, 1579, 1632, 1639, 1659, 1680, 1683, 1691, 1709, 1714, 1753, 17 71, 1826, 1855, 1856, 1890, 1924, 1935, 1948, 1979, 1980, 2170, 2288, 2331, 2339, 2340,数据结构容易：1182, 1656, 2021, 2023, 2051, 2153, 2227, 2236, 2247, 2352, 2395,不易：1145, 1177, 1195, 1227, 1661, 1834,推荐：1330, @1338, 1451, 1470, 1634, 1689, 1693, @1703, 1724, 1988, 2004, 2010(堆), 2119, 2274,动态规划容易：1018, 1050, 1083, 1088, 1125, 1143（博弈树）, 1157, @1163, 1178, 1179, @1189, 1208, 1276, 1322, 1414, 1456, 1458, 1609, 1644, 1664, 1690, 1699, 1740, 1742, 1887, 1926, 19 36, 1952, 1953, 1958, 1959, 1962, 1975, 1989, 2018, 2029, 2033, 2063, 2081, 2082, 2181, 2184, 2192, 2231, 2279, 2329, 2336, 2346, 2353, 2355, 2356, 2385, 2392, 2424,不易：1019, 1037, 1080, 1112, 1141, 1170, 1192, 1239, 1655, 1695, 1707, 1733, 1737, 1837, 18 50, 1920, 1934, 1937, 1964, 2039, 2138, 2151, 2161, 2178,推荐：1015, 1635, 1636, 1671, 1682, 1692, 1704, 1717, 1722, 1726, 1732, 1770, 1821, 1853, 19 49, 2019, 2127, 2176, 2228, 2287, 2342, 2374, 2378, 2384, 2411,字符串：1488, ⊙1598, 1686, *1706, 1747, 1748, 1750, 1760, 1782, 1790, 1866, 1888, 1896, 1951, 2003, 2121, 2141, 2145, 2159, 2337, 2359, 2372, 2406, 2408,贪心：1042, 1065, 1230, 1323, 1477, 1716, 1784,图论容易：1161, 1164, 1258, 1175, 1308, 1364, 1776, 1789, 1861, 1939, 1940, 1943, 2075, 2139, 23 87, 2394, 2421,不易：1041, 1062, 1158, 1172, 1201, 1275, 1718, 1734, 1751, 1904, 1932, 2173, 2175, 2296,网络流：1087, 1273, 1698, 1815, 2195,匹配：1274, 1422, 1469, 1719, 2060, 2239,Euler：1237, 1637, 1394, 2230,推荐：2049, 2186,计算几何容易：@1319, @1654, @1673, @1675, 1836, 2074, 2137, 2318,不易：1685, 1687, 1696, 1873, 1901, 2172, 2333,凸包：1113, 1228, 1794, 2007, 2187,模拟容易：1006, 1008, 1013, 1016, 1017, 1169, 1298, 1326, 1350, 1363, 1676, 1786, 1791, 1835, 19 70, 2317, 2325, 2390,不易：1012, 1082, 1099, 1114, 1642, 1677, 1684, 1886,数学容易：@1061, @1091, @1142, 1289, @1305, @1306, 1320, @1565, @1665, 1666, @1730, @18 94, @1914, 2006, @2042, @2142, 2158, 2174, @2262, @2305, @2321, @2348,不易：@1067, @1183, 1430, 1759, 1868, 1942, 2167, 2171, 2327,推荐：@1423, 1450, 1640, @1702, 1710, 1721, 1761, 1830, @1930, @2140,（三）：1、排序1423, 1694, 1723, 1727, 1763, 1788, 1828, 1838, 1840, 2201, 2376, 2377, 2380, 1318, 18 77, 1928, 1971, 1974, 1990, 2001, 2002, 2092, 2379, 1002（需要字符处理，排序用快排即可）1007（稳定的排序）2159（题意较难懂）2231 2371（简单排序）2388（顺序统计算法）2418（二叉排序树）2、搜索、回溯、遍历1022 1111 1118 1129 1190 1562 1564 1573 1655 2184 2225 2243 2312 2362 2378 2386 1010,1011,1018,1020,1054,1062,1256,1321,1363,1501,1650,1659,1664,1753,2078,2083,2303,2 310,2329简单：1128, 1166, 1176, 1231, 1256, 1270, 1321, 1543, 1606, 1664, 1731, 1742, 1745, 18 47, 1915, 1950, 2038, 2157, 2182, 2183, 2381, 2386, 2426,不易：1024, 1054, 1117, 1167, 1708, 1746, 1775, 1878, 1903, 1966, 2046, 2197, 2349,推荐：1011, 1190, 1191, 1416, 1579, 1632, 1639, 1659, 1680, 1683, 1691, 1709, 1714, 17 53, 1771, 1826, 1855, 1856, 1890, 1924, 1935, 1948, 1979, 1980, 2170, 2288, 2331, 2339, 2340,1979（和迷宫类似）1980（对剪枝要求较高）3、历法1008 2080 （这种题要小心）4、枚举1012，1046，1387，1411，2245，2326，2363，2381，1054（剪枝要求较高），165 0 （小数的精度问题）5、数据结构的典型算法容易：1182, 1656, 2021, 2023, 2051, 2153, 2227, 2236, 2247, 2352, 2395,不易：1145, 1177, 1195, 1227, 1661, 1834,推荐：1330, 1338, 1451, 1470, 1634, 1689, 1693, 1703, 1724, 1988, 2004, 2010, 2119, 22 74,1125(弗洛伊德算法) ，2421（图的最小生成树）6、动态规划1037、1050、1088、1125、1141、1159、1160、1163、1458、1579 、1887 、1953 、2386 7、贪心1042, 1065, 1230, 1323, 1477, 1716, 1784,1328 1755（或用单纯形方法），2054，1017，1328，1862，1922 ，2209，2313，2325，2370。

简单题1000A+B Problem1001Exponentiation1003 Hangover1004 Financial Management1005 I Think I Need a Houseboat1005 Biorhythms1007 DNA Sorting1013 Counterfeit Dollar1014 Dividing1032 Parliament1045 Bode Plot1119 Start Up the Startup1131 Octal Fractions1142 Smith Numbers1151 Atlantis1152 An Easy Problem!1188 Gleaming the Cubes1207 The 3n + 1 problem1218 the drunk jailer1220 number base conversion1242 Plugged In1256 Anagram1308 Is It A Tree?1316 Self Numbers1318 Word Amalgamation1338 Ugly Numbers1406 A Starship Hakodate-maru1411 Calling Extraterrestrial Intelligence Again 1451 T91455 Crazy tea party1468 Rectangles1477 Box of Bricks1491 Pi1517 u Calculate e1519 Digital Roots1528 Perfection1547 Clay Bully1552 Doubles1564 Sum It Up1579 Function Run Fun1595 Prime Cuts1597 Uniform Generator1658 Eva's Problem1663 Number Steps1664 放苹果1665 Biker's Trip Odometer1730 Perfect Pth Powers1731 Orders1775 Sum of Factorials1828 Monkeys' Pride1833 排列1856 Sea Battle1906 Three powers1920 Ride to School1929 Calories from Fat1936 All in All1942 Paths on a Grid1951 Extra Krunch1953 World Cup Noise1959 Darts1965 Cube Root1969 Count on Canton1970 The Game1979 Red and Black1992 Jack1993 Caleidoscope1995 Raising Modulo Numbers1996 The Highest Profits1998 Lloyd Fifteen Puzzle2000 Gold Coins2013 Symmetric Order2017 Speed Limit2021 Relative Relatives2027 No Brainer2038 Team Rankings2042 Lagrange's Four-Square Theorem2059 Watchdog2060 Taxi Cab Scheme2062Card Game Cheater2070 Filling Out the Team2105 IP Address2126 Factoring a Polynomial2128 Highways2136 Vertical Histogram2183 Bovine Math Geniuses2209 The King2273 An Excel-lent Problem2275 Flipping Pancake2276 Model Rocket Height2291 Rotten Ropes2299 Ultra-QuickSort2316 SPIN2323 PERMS2325 Persistent Numbers2402 Palindrome Numbers搜索题1011 Sticks1419 Graph Coloring1683 Puzzlestan 1889 Package Pricing1980 Unit Fraction Partition2147 Dice Puzzle模拟题1012 Joseph1099 Square Ice1115 Statistical Trouble1598 Excuses, Excuses!1666 Candy Sharing Game1668 Taxation With Representation Overdone 1676 What time is it?1677 Girls' Day1680 Fork() Makes Trouble1684 Dynamic Declaration Language (DDL)1690 (Your)((Term)((Project)))1748 Computer Dialogue1749 Lock Manager1750 Dictionary1760 Disk Tree1768 Hang or not to hang1880 Variable Radix Huffman Encoding1885 Uncompress1886 Borrowers1888 Crossword Answers1910 Adam's Genes1919 Ship Journey1939 Diplomatic License1940 Polygon Programming with Ease1955 Rubik's Cube1960 Time Planner1978 Hanafuda Shuffle2014 Flow Layout2022 Syntax Included2023 Choose Your Own Adventure2039 To and Fro2050 Searching the Web2051 Argus2078 Matrix2081 Recaman's Sequence2106 Boolean Expressions2159 Ancient Cipher2162 Document Indexing2174 Decoding Task2219 Manifest Destiny2317 SHAKE2319 COMPRESS2324 Intellectual Property2326 Major Scales2334 Simple prefix compression 2338 Basic2341 Spell checker动态规划1015 Jury Compromise1018 Communication System1038 Bugs Integrated, Inc.1085 Triangle War1088 滑雪1159 Palindrome1163 The Triangle1171 Letter Game1185炮兵阵地1187 陨石的秘密1191 棋盘分割1229 Wild Domains1239 Increasing Sequences1243 One Person1402 The Game of Master-Mind1417 True Liars1426 Find The Multiple1458 Common Subsequence1508 Skyscraper Floors1580 String Matching1608 Banal Tickets1678 I Love this Game!1682 Clans on the Three Gorges1691 Painting A Board1692 Crossed Matchings1694 An Old Stone Game1695 Magazine Delivery1701 Dissatisfying Lift1717 Dominoes1722 SUBTRACT1732 Phone numbers1733 Parity game1742 Coins1744 Elevator Stopping Plan1745 Divisibility1752 Advertisement1754 Buffer Manager1758 Frontier1769 Minimizing maximizer1770 Special Experiment1777 Vivian's Problem1829 火力防御网1836 Alignment1837 Balance1838 Banana1839 Cattle1840 Eqs1844 Sum1848 Tree1849 Two1874 Trade on Verweggistan1887 Testing the CATCHER1890 Switching Channels1933 A Brief Gerrymander1934 Trip1938 California Jones and the Gate to Freedom1943 Hall of Fountains1946 Cow Cycling1947 Rebuilding Roads1948 Triangular Pastures1949 Chores1950 Dessert1952 buy low, buy lower1958 Strange Towers of Hanoi1973 Software Company1976 A Mini Locomotive1984 Navigation Nightmare1985 Cow Marathon1986 Distance Queries1991 Turning in Homework2004 Mix and Build2018 Best Cow Fences2019 Cornfields2057 The Lost House2082 Terrible Sets2111 Millenium Leapcow2127 Greatest Common Increasing Subsequence2133 Cow Imposters2138 Travel Games2146 Confusing Login Names2161 Chandelier2163 Easy Trading2168 Joke with Turtles2176 Folding2178 Heroes Of Might And Magic2182 Lost Cows2188 Cow Laundry2189 Romeo Meets Juliet2204 Commuter train2237 Can 1 Marine win 2 Zerglings? 2238 Computer Basketball Game2283 Different Digits2292 Optimal Keypad2300 Up the Ante2303 Russian Dolls2322 PLANKS2329 Nearest number - 22332 One is good, but two is better2355 Railway tickets2364 Faucet Flow2422 The Wolves and the Sheep2430 Lazy Cows计算几何1031 Fence1039 Pipe1066 Treasure Hunt 1266 Cover an Arc.1271 Nice Milk1556 The Doors 1654 Area1673 EXOCENTEROF A TRIANGLE1675 Happy Birthday!1687 Buggy Sat1688 Dolphin Pool1696 Space Ant 1755 Triathlon1931 Biometrics1937 Balanced Food1971 Parallelogram Counting1981 Circle and Points2007 Scrambled Polygon 2008 Moo University - Team Tryouts2010 Moo University - Financial Aid2026 As the Crow Flies2074 Line of Sight2164 Find the Border2333 Beach cut2365 Rope2416 Return of the Jedi递推1037 A decorative fence1050 To the Max1074 Parallel Expectations 1090 Chain1147 Binary codes1153 SAFE1205 Water Treatment Plants1309 Coconuts, Revisited1671 Rhyme Schemes 1832 连环锁1850 Code2084 Game of Connections 2096 Collecting Bugs数学题1061 青蛙的约会1067 取石子游戏1145 Tree Summing1146 ID Codes1166 The Clocks1183 反正切函数的应用1286 Necklace of Beads1322 Chocolate1363 Rails1401 Factorial1423 Big Number1430 Binary Stirling Numbers1433 Exchanges1507 Commedia dell' arte1604 Just the Facts1633 Gladiators1662 CoIns1674 Sorting by Swapping1693 Counting Rectangles1702 Eva's Balance1711 Puncher1721 CARDS1728 A flea on a chessboard1737 Connected Graph1753 Flip Game1757 Binary Search1759 Garland1767 Which is Next1788 Building a New Depot1799 Yeehaa!1830 开关问题1845 Sumdiv1846 System1859 The Perfect Symmetry1870 Bee Breeding1879 Tempus et mobilius Time and motion 1990 MooFest2085 Inversion2100 Graveyard Design2101 Honey and Milk Land2115 C Looooops2116 Death to Binary?2154 Color2158 A Difficult Mathematics Problem2305 Basic remains2345 Central heating2356 Find a multiple2407 Relatives2409 Let it Bead2417 Discrete Logging2420 A Star not a Tree?图论1062 昂贵的聘礼1276 Cash Machine1292 Will Indiana Jones Get There?1378 Power Cable Problem1635 Subway tree systems1637 Sightseeing tour1685 Color Tunnels1689 3002 Rubbery1697 The Erythea Campaign1724 ROADS1729 Jack and Jill1734 Sightseeing trip1751 Highways1756 Domino Puzzle1761 Easy Task1797 Heavy Transportation1847 Tram1860 Currency Exchange1878 Jill's Bike1904 King's Quest1932 XYZZY1935 Journey1975 Median Weight Bead2110 Mountain Walking2135 Farm Tour2169 Kingdom of Magic2186 Popular Cows2202 Strange Graph2230 Watchcow2233 Game again!2236 Wireless Network2267 From Dusk till Dawn or: Vladimir the Vampire2337 Catenyms2357 Labyrinth2187 Til the Cows Come Home生成树1258 Agri-Net1639 Picnic Planning1679 The Unique MST1841 Meadow网络流1459 Power Network2125 Destroying The Graph2239 Selecting Courses 2226 Muddy Fields2289 Jamie's Contact Groups数据结构1182 食物链1442 Black Box1703 Find them, Catch them 1765 November Rain1823 Hotel1961 Period1988 Cube Stacking2104 K-th Number2123 Key Insertion2166 Heapsort2185 Milking Grid2201 Cartesian Tree 2383 Circle Drawing2388 Who's in the Middle2406 Power Strings贪心1456 Supermarket1700 Crossing River1716 Integer Intervals1727 Advanced Causal Measurements (ACM)1771 Elevator Stopping Plan1818 ATP1826 The Best Farm1827 A Bunch Of Monsters1842 Parking1862 Stripies1873 The Fortified Forest1967 Alibaba1974 The Happy Worm2054 Color a Tree2232 New Stone-Forfex-Cloth Game 2313 Sequence2376 Cleaning Shifts2431 Expedition构造1672 Fully Diversified Sequences of Sets1747 Expression1776 Task Sequences 1831 不定方程组1898 Entropy枚举1681 Painter's Problem1868 Antiarithmetic?特殊问题特殊对待1669 It's Logical1686 Lazy Math Instructor1863 Subnumber1920 Towers of Hanoi1930 Dead Fraction1941 The Sierpinski Fractal 1944 Fiber Communications9164 City Game1982Water Tank1983 Name the Crossing1989 The Cow Lineup2045 Molecular Formula2058 Word Encoding2061 Pseudo-random Numbers2083 Fractal2277 Model Rocket Height2328 Guessing Game博弈1704 Georgia and Bob1740 A New Stone Game2234 Matches Game 2425 A Chess Game。

初期:一.基本算法:(1)枚举. (poj1753,poj2965)(2)贪心(poj1328,poj2109,poj2586)(3)递归和分治法.(4)递推.(5)构造法.(poj3295)(6)模拟法.(poj1068,poj2632,poj1573,poj2993,poj2996)二.图算法:(1)图的深度优先遍历和广度优先遍历.(2)最短路径算法(dijkstra,bellman-ford,floyd,heap+dijkstra)(poj1860,poj3259,poj1062,poj2253,poj1125,poj2240)(3)最小生成树算法(prim,kruskal) (poj1789,poj2485,poj1258,poj3026)(4)拓扑排序 (poj1094)(5)二分图的最大匹配 (匈牙利算法) (poj3041,poj3020)(6)最大流的增广路算法(KM算法). (poj1459,poj3436)三.数据结构.(1)串 (poj1035,poj3080,poj1936)(2)排序(快排、归并排(与逆序数有关)、堆排) (poj2388,poj2299)(3)简单并查集的应用.(4)哈希表和二分查找等高效查找法(数的Hash,串的Hash)(poj3349,poj3274,POJ2151,poj1840,poj2002,poj2503)(5)哈夫曼树(poj3253)(6)堆(7)trie树(静态建树、动态建树) (poj2513)四.简单搜索(1)深度优先搜索 (poj2488,poj3083,poj3009,poj1321,poj2251)(2)广度优先搜索(poj3278,poj1426,poj3126,poj3087.poj3414)(3)简单搜索技巧和剪枝(poj2531,poj1416,poj2676,1129)五.动态规划(1)背包问题. (poj1837,poj1276)(2)型如下表的简单DP(可参考lrj的书 page149):1.E[j]=opt{D+w(i,j)} (poj3267,poj1836,poj1260,poj2533)2.E[i,j]=opt{D[i-1,j]+xi,D[i,j-1]+yj,D[i-1][j-1]+zij} (最长公共子序列) (poj3176,poj1080,poj1159)3.C[i,j]=w[i,j]+opt{C[i,k-1]+C[k,j]}.(最优二分检索树问题)六.数学(1)组合数学:1.加法原理和乘法原理.2.排列组合.3.递推关系.(POJ3252,poj1850,poj1019,poj1942)(2)数论.1.素数与整除问题2.进制位.3.同余模运算.(poj2635, poj3292,poj1845,poj2115)(3)计算方法.1.二分法求解单调函数相关知识.(poj3273,poj3258,poj1905,poj3122)七.计算几何学.(1)几何公式.(2)叉积和点积的运用(如线段相交的判定,点到线段的距离等). (poj2031,poj1039)(3)多边型的简单算法(求面积)和相关判定(点在多边型内,多边型是否相交)(poj1408,poj1584)(4)凸包. (poj2187,poj1113)中级:一.基本算法:(1)C++的标准模版库的应用. (poj3096,poj3007)(2)较为复杂的模拟题的训练(poj3393,poj1472,poj3371,poj1027,poj2706)二.图算法:(1)差分约束系统的建立和求解. (poj1201,poj2983)(2)最小费用最大流(poj2516,poj2516,poj2195)(3)双连通分量(poj2942)(4)强连通分支及其缩点.(poj2186)(5)图的割边和割点(poj3352)(6)最小割模型、网络流规约(poj3308, )三.数据结构.(1)线段树. (poj2528,poj2828,poj2777,poj2886,poj2750)(2)静态二叉检索树. (poj2482,poj2352)(3)树状树组(poj1195,poj3321)(4)RMQ. (poj3264,poj3368)(5)并查集的高级应用. (poj1703,2492)(6)KMP算法. (poj1961,poj2406)四.搜索(1)最优化剪枝和可行性剪枝(2)搜索的技巧和优化 (poj3411,poj1724)(3)记忆化搜索(poj3373,poj1691)五.动态规划(1)较为复杂的动态规划(如动态规划解特别的施行商问题等) (poj1191,poj1054,poj3280,poj2029,poj2948,poj1925,poj3034)(2)记录状态的动态规划. (POJ3254,poj2411,poj1185)(3)树型动态规划(poj2057,poj1947,poj2486,poj3140)六.数学(1)组合数学:1.容斥原理.2.抽屉原理.3.置换群与Polya定理(poj1286,poj2409,poj3270,poj1026).4.递推关系和母函数.(2)数学.1.高斯消元法(poj2947,poj1487, poj2065,poj1166,poj1222)2.概率问题. (poj3071,poj3440)3.GCD、扩展的欧几里德(中国剩余定理) (poj3101)(3)计算方法.1.0/1分数规划. (poj2976)2.三分法求解单峰(单谷)的极值.3.矩阵法(poj3150,poj3422,poj3070)4.迭代逼近(poj3301)(4)随机化算法(poj3318,poj2454)(5)杂题. (poj1870,poj3296,poj3286,poj1095)七.计算几何学.(1)坐标离散化.(2)扫描线算法(例如求矩形的面积和周长并,常和线段树或堆一起使用).(poj1765,poj1177,poj1151,poj3277,poj2280,poj3004)(3)多边形的内核(半平面交)(poj3130,poj3335)(4)几何工具的综合应用.(poj1819,poj1066,poj2043,poj3227,poj2165,poj3429)高级:一.基本算法要求:(1)代码快速写成,精简但不失风格(poj2525,poj1684,poj1421,poj1048,poj2050,poj3306)(2)保证正确性和高效性. poj3434二.图算法:(1)度限制最小生成树和第K最短路. (poj1639)(2)最短路,最小生成树,二分图,最大流问题的相关理论(主要是模型建立和求解) (poj3155, poj2112,poj1966,poj3281,poj1087,poj2289,poj3216,poj2446) (3)最优比率生成树. (poj2728)(4)最小树形图(poj3164)(5)次小生成树.(6)无向图、有向图的最小环三.数据结构.(1)trie图的建立和应用. (poj2778)(2)LCA和RMQ问题(LCA(最近公共祖先问题) 有离线算法(并查集+dfs) 和在线算法(RMQ+dfs)).(poj1330)(3)双端队列和它的应用(维护一个单调的队列,常常在动态规划中起到优化状态转移的目的).(poj2823)(4)左偏树(可合并堆).(5)后缀树(非常有用的数据结构,也是赛区考题的热点). (poj3415,poj3294)四.搜索(1)较麻烦的搜索题目训练(poj1069,poj3322,poj1475,poj1924,poj2049,poj3426)(2)广搜的状态优化:利用M进制数存储状态、转化为串用hash表判重、按位压缩存储状态、双向广搜、A*算法. (poj1768,poj1184,poj1872,poj1324,poj2046,poj1482)(3)深搜的优化:尽量用位运算、一定要加剪枝、函数参数尽可能少、层数不易过大、可以考虑双向搜索或者是轮换搜索、IDA*算法.(poj3131,poj2870,poj2286)五.动态规划(1)需要用数据结构优化的动态规划. (poj2754,poj3378,poj3017)(2)四边形不等式理论.(3)较难的状态DP(poj3133)六.数学(1)组合数学.1.MoBius反演(poj2888,poj2154)2.偏序关系理论.(2)博奕论.1.极大极小过程(poj3317,poj1085)2.Nim问题.七.计算几何学.(1)半平面求交(poj3384,poj2540)(2)可视图的建立(poj2966)(3)点集最小圆覆盖.(4)对踵点(poj2079)八.综合题.(poj3109,poj1478,poj1462,poj2729,poj2048,poj3336,poj3315,poj2148,poj1263) 以及补充Dp状态设计与方程总结1.不完全状态记录<1>青蛙过河问题<2>利用区间dp2.背包类问题<1> 0-1背包，经典问题<2>无限背包，经典问题<3>判定性背包问题<4>带附属关系的背包问题<5> + -1背包问题<6>双背包求最优值<7>构造三角形问题<8>带上下界限制的背包问题(012背包)3.线性的动态规划问题<1>积木游戏问题<2>决斗（判定性问题）<3>圆的最大多边形问题<4>统计单词个数问题<5>棋盘分割<6>日程安排问题<7>最小逼近问题(求出两数之比最接近某数/两数之和等于某数等等)<8>方块消除游戏(某区间可以连续消去求最大效益)<9>资源分配问题<10>数字三角形问题<11>漂亮的打印<12>邮局问题与构造答案<13>最高积木问题<14>两段连续和最大<15>2次幂和问题<16>N个数的最大M段子段和<17>交叉最大数问题4.判定性问题的dp(如判定整除、判定可达性等)<1>模K问题的dp<2>特殊的模K问题，求最大(最小)模K的数<3>变换数问题5.单调性优化的动态规划<1>1-SUM问题<2>2-SUM问题<3>序列划分问题(单调队列优化)6.剖分问题(多边形剖分/石子合并/圆的剖分/乘积最大)<1>凸多边形的三角剖分问题<2>乘积最大问题<3>多边形游戏(多边形边上是操作符,顶点有权值)<4>石子合并(N^3/N^2/NLogN各种优化)7.贪心的动态规划<1>最优装载问题<2>部分背包问题<3>乘船问题<4>贪心策略<5>双机调度问题Johnson算法8.状态dp<1>牛仔射击问题(博弈类)<2>哈密顿路径的状态dp<3>两支点天平平衡问题<4>一个有向图的最接近二部图9.树型dp<1>完美服务器问题(每个节点有3种状态)<2>小胖守皇宫问题<3>网络收费问题<4>树中漫游问题<5>树上的博弈<6>树的最大独立集问题<7>树的最大平衡值问题<8>构造树的最小环转一个搞ACM需要的掌握的算法.要注意,ACM的竞赛性强,因此自己应该和自己的实际应用联系起来.适合自己的才是好的,有的人不适合搞算法,喜欢系统架构,因此不要看到别人什么就眼红, 发挥自己的长处,这才是重要的.第一阶段：练经典常用算法，下面的每个算法给我打上十到二十遍，同时自己精简代码，因为太常用，所以要练到写时不用想，10-15分钟内打完，甚至关掉显示器都可以把程序打出来.1.最短路(Floyd、Dijstra,BellmanFord)2.最小生成树(先写个prim,kruscal要用并查集，不好写)3.大数（高精度）加减乘除4.二分查找. (代码可在五行以内)5.叉乘、判线段相交、然后写个凸包.6.BFS、DFS,同时熟练hash表(要熟，要灵活,代码要简)7.数学上的有：辗转相除（两行内），线段交点、多角形面积公式.8. 调用系统的qsort, 技巧很多，慢慢掌握.9. 任意进制间的转换第二阶段：练习复杂一点，但也较常用的算法。

1000 A+B Problem 送分题1001 Exponentiation 高精度1003 Hangover 送分题1004 Financial Management 送分题1005 I Think I Need a Houseboat 几何1006 Biorhythms 送分题1007 DNA Sorting 送分题1008 Maya Calendar 日期处理1010 STAMPS 搜索＋DP1011 Sticks 搜索1012 Joseph 模拟/数学方法1014 Dividing 数论/DP?/组合数学->母函数?1015 Jury Compromise DP1016 Numbers That Count 送分题1017 Packets 贪心1018 Communication System 贪心1019 Number Sequence 送分题1020 Anniversary Cake 搜索1023 The Fun Number System 数论1025 Department 模拟1026 Cipher 组合数学1027 The Same Game 模拟1028 Web Navigation 送分题1031 Fence 计算几何1034 The dog task 计算几何1037 A decorative fence DP/组合数学1039 Pipe 几何1042 Gone Fishing 贪心/DP1045 Bode Plot 送分题(用物理知识)1046 Color Me Less 送分题1047 Round and Round We Go 高精度1048 Follow My Logic 模拟1049 Microprocessor Simulation 模拟1050 To the Max DP1053 Set Me 送分题1054 The Troublesome Frog 搜索1060 Modular multiplication of polynomials 高精度1061 青蛙的约会数论1062 昂贵的聘礼DP1064 Cable master DP/二分查找1065 Wooden Sticks DP1067 取石子游戏博弈论1068 Parencodings 送分题1069 The Bermuda Triangle 搜索1070 Deformed Wheel 几何1071 Illusive Chase 送分题1072 Puzzle Out 搜索1073 The Willy Memorial Program 模拟1074 Parallel Expectations DP1075 University Entrance Examination 模拟1080 Human Gene Functions DP->LCS变形1082 Calendar Game 博弈论1084 Square Destroyer 搜索？1085 Triangle War 博弈论1086 Unscrambling Images 模拟?1087 A Plug for UNIX 图论->最大流1088 滑雪DFS/DP1090 Chain ->格雷码和二进制码的转换1091 跳蚤数论1092 Farmland 几何1093 Formatting Text DP1094 Sorting It All Out 图论->拓扑排序1095 Trees Made to Order 组合数学1096 Space Station Shielding 送分题1097 Roads Scholar 图论1098 Robots 模拟1099 Square Ice 送分题1100 Dreisam Equations 搜索1101 The Game 搜索->BFS1102 LC-Display 送分题1103 Maze 模拟1104 Robbery 递推1106 Transmitters 几何1107 W's Cipher 送分题1110 Double Vision 搜索1111 Image Perimeters 搜索1112 Team Them Up! DP1113 Wall 计算几何->convex hull1119 Start Up the Startup 送分题1120 A New Growth Industry 模拟1122 FDNY to the Rescue! 图论->Dijkstra 1125 Stockbroker Grapevine 图论->Dijkstra 1128 Frame Stacking 搜索1129 Channel Allocation 搜索（图的最大独立集）1131 Octal Fractions 高精度1135 Domino Effect 图论->Dijkstra1137 The New Villa 搜索->BFS1141 Brackets Sequence DP1142 Smith Numbers 搜索1143 Number Game 博弈论1147 Binary codes 构造1148 Utopia Divided 构造1149 PIGS 图论->网络流1151 Atlantis 计算几何->同等安置矩形的并的面积->离散化1152 An Easy Problem! 数论1157 LITTLE SHOP OF FLOWERS DP1158 TRAFFIC LIGHTS 图论->Dijkstra变形1159 Palindrome DP->LCS1160 Post Office DP1161 Walls 图论1162 Building with Blocks 搜索1163 The Triangle DP1170 Shopping Offers DP1177 Picture 计算几何->同等安置矩形的并的周长->线段树1179 Polygon DP1180 Batch Scheduling DP1182 食物链数据结构->并查集1183 反正切函数的应用搜索1184 聪明的打字员搜索1185 炮兵阵地DP->数据压缩1187 陨石的秘密DP（BalkanOI99 Par的拓展）1189 钉子和小球递推?1190 生日蛋糕搜索/DP1191 棋盘分割DP1192 最优连通子集图论->无负权回路的有向图的最长路->BellmanFord 1193 内存分配模拟1194 HIDDEN CODES 搜索+DP1197 Depot 数据结构->Young T ableau1201 Intervals 贪心/图论->最长路->差分约束系统1202 Family 高精度1209 Calendar 日期处理1217 FOUR QUARTERS 递推1218 THE DRUNK JAILER 送分题1233 Street Crossing 搜索->BFS1245 Programmer, Rank Thyself 送分题1247 Magnificent Meatballs 送分题1248 Safecracker 搜索1250 T anning Salon 送分题1251 Jungle Roads 图论->最小生成树1271 Nice Milk 计算几何1273 Drainage Ditches 图论->最大流1274 The Perfect Stall 图论->二分图的最大匹配1275 Cashier Employment 图论->差分约束系统->无负权回路的有向图的最长路->Bellman-Ford1280 Game 递推1281 MANAGER 模拟1286 Necklace of Beads 组合数学->Polya定理1288 Sly Number 数论->解模线性方程组1293 Duty Free Shop DP1298 The Hardest Problem Ever 送分题1316 Self Numbers 递推同Humble Number一样1322 Chocolate 递推/组合数学1323 Game Prediction 贪心1324 Holedox Moving BFS+压缩储存1325 Machine Schedule 图论->二分图的最大匹配1326 Mileage Bank 送分题1327 Moving Object Recognition 模拟?1328 Radar Installation 贪心（差分约束系统的特例）1338 Ugly Numbers 递推(有O(n)算法)1364 King 图论->无负权回路的有向图的最长路->BellmanFord1370 Gossiping (数论->模线性方程有无解的判断)+(图论->DFS)2184 Cow Exhibition DP2190 ISBN 送分题2191 Mersenne Composite Numbers 数论2192 Zipper DP->LCS变形2193 Lenny's Lucky Lotto Lists DP2194 Stacking Cylinders 几何2195 Going Home 图论->二分图的最大权匹配2196 Specialized Four-Digit Numbers 送分题2197 Jill's Tour Paths 图论->2199 Rate of Return 高精度2200 A Card Trick 模拟2210 Metric Time 日期处理2239 Selecting Courses 图论->二分图的最大匹配2243 Knight Moves 搜索->BFS2247 Humble Numbers 递推(最优O(n)算法)2253 Frogger 图论->Dijkstra变形(和1295是一样的)2254 Globetrotter 几何2261 France '98 递推2275 Flipping Pancake 构造2284 That Nice Euler Circuit 计算几何2289 Jamie's Contact Groups 图论->网络流?2291 Rotten Ropes 送分题2292 Optimal Keypad DP2299 Ultra-QuickSort 排序->归并排序2304 Combination Lock 送分题2309 BST 送分题2311 Cutting Game 博弈论2312 Battle City 搜索->BFS2314 POJ language 模拟2315 Football Game 几何2346 Lucky tickets 组合数学2351 Time Zones 时间处理2379 ACM Rank T able 模拟+排序2381 Random Gap 数论2385 Apple Catching DP(像NOI98“免费馅饼”)2388 Who's in the Middle 送分题(排序)2390 Bank Interest 送分题2395 Out of Hay 图论->Dijkstra变形2400 Supervisor, Supervisee 图论->二分图的最大权匹配?2403 Hay Points 送分题2409 Let it Bead 组合数学->Polya定理2416 Return of the Jedi 图论->2417 Discrete Logging 数论2418 Hardwood Species 二分查找2419 Forests 枚举2421 Constructing Roads 图论->最小生成树2423 The Parallel Challenge Ballgame 几何2424 Flo's Restaurant 数据结构->堆2425 A Chess Game 博弈论2426 Remainder BFS2430 Lazy Cows DP->数据压缩1375 Intervals 几何1379 Run Away 计算几何->1380 Equipment Box 几何1383 Labyrinth 图论->树的最长路1394 Railroad 图论->Dijkstra1395 Cog-Wheels 数学->解正系数的线性方程组1408 Fishnet 几何1411 Calling Extraterrestrial Intelligence Again 送分题1430 Binary Stirling Numbers 日期处理1431 Calendar of Maya 模拟1432 Decoding Morse Sequences DP1434 Fill the Cisterns! 计算几何->离散化/1445 Random number 数据结构->碓1447 Ambiguous Dates 日期处理1450 Gridland 图论(本来TSP问题是NP难的，但这个图比较特殊，由现成的构造方法)1458 Common Subsequence DP->LCS1459 Power Network 图论->最大流1462 Random Walk 模拟+解线性方程组1463 Strategic game 贪心1466 Girls and Boys 图论->n/a1469 COURSES 贪心1475 Pushing Boxes DP1476 Always On the Run 搜索->BFS1480 Optimal Programs 搜索->BFS1481 The Die Is Cast 送分题1482 It's not a Bug, It's a Feature! 搜索->BFS1483 Going in Circles on Alpha Centauri 模拟1484 Blowing Fuses 送分题1485 Fast Food DP(似乎就是ioi2000的postoffice)1486 Sorting Slides 图论->拓扑排序1505 Copying Books DP+二分查找1510 Hares and Foxes 数论1512 Keeps Going and Going and ... 模拟1513 Scheduling Lectures DP1514 Metal Cutting 几何1515 Street Directions 图论->把一个无向连通图改造成为有向强连通图1517 u Calculate e 送分题1518 Problem Bee 几何1519 Digital Roots 送分题(位数可能很大)1520 Scramble Sort 排序1547 Clay Bully 送分题1555 Polynomial Showdown 送分题(非常阴险)1563 The Snail 送分题1601 Pizza Anyone? 搜索1604 Just the Facts 送分题1605 Horse Shoe Scoring 几何1606 Jugs 数论/搜索1631 Bridging signals DP+二分查找1632 Vase collection 图论->最大完全图1633 Gladiators DP1634 Who's the boss? 排序1635 Subway tree systems 图论->不同表示法的二叉树判同1637 Sightseeing tour 图论->欧拉回路1638 A number game 博弈论1639 Picnic Planning 图论->1641 Rational Approximation 数论1646 Double Trouble 高精度1654 Area 几何1657 Distance on Chessboard 送分题1658 Eva's Problem 送分题1660 Princess FroG 构造1661 Help Jimmy DP1663 Number Steps 送分题1664 放苹果组合数学->递推1677 Girls' Day 送分题1688 Dolphin Pool 计算几何1690 (Your)((Term)((Project))) 送分题1691 Painting A Board 搜索/DP1692 Crossed Matchings DP1693 Counting Rectangles 几何1694 An Old Stone Game 博弈论?1695 Magazine Delivery 图论->1712 Flying Stars DP1713 Divide et unita 搜索1714 The Cave 搜索/DP1717 Dominoes DP1718 River Crossing DP1719 Shooting Contest 贪心1729 Jack and Jill 图论->1730 Perfect Pth Powers 数论1732 Phone numbers DP1734 Sightseeing trip 图论->Euler回路1738 An old Stone Game 博弈论?1741 Tree 博弈论?1745 Divisibility DP1751 Highways 图论->1752 Advertisement 贪心/图论->差分约束系统1753 Flip Game 搜索->BFS1755 Triathlon 计算几何?1770 Special Experiment 树形DP1771 Elevator Stopping Plan DP1772 New Go Game 构造?1773 Outernet 模拟1774 Fold Paper Strips 几何1775 Sum of Factorials 送分题1776 T ask Sequences DP1777 Vivian's Problem 数论1870 Bee Breeding 送分题1871 Bullet Hole 几何1872 A Dicey Problem BFS1873 The Fortified Forest 几何+回溯1874 Trade on Verweggistan DP1875 Robot 几何1876 The Letter Carrier's Rounds 模拟1877 Flooded! 数据结构->堆1879 Tempus et mobilius Time and motion 模拟+组合数学->Polya定理1882 Stamps 搜索+DP1883 Theseus and the Minotaur 模拟1887 Testing the CATCHER DP1889 Package Pricing DP1893 Monitoring Wheelchair Patients 模拟+几何1915 Knight Moves 搜索->BFS1916 Rat Attack 数据结构->?1936 All in All DP?1946 Cow Cycling DP1947 Rebuilding Roads 二分1985 Cow Marathon 图论->有向无环图的最长路1995 Raising Modulo Numbers 数论->大数的幂求余2049 Finding Nemo 图论->最短路2050 Searching the Web 模拟(需要高效实现)2051 Argus 送分题(最好用堆，不用也可以过)2054 Color a Tree 贪心2061 Pseudo-random Numbers 数论2080 Calendar 日期处理2082 Terrible Sets 分治/2083 Fractal 递归2084 Game of Connections 递推(不必高精度)2105 IP Address 送分题2115 C Looooops 数论->解模线性方程2136 Vertical Histogram 送分题2165 Gunman 计算几何2179 Inlay Cutters 枚举2181 Jumping Cows 递推2182 Lost Cows ->线段树/＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝1370 Gossiping (数论->模线性方程有无解的判断)+(图论->DFS)1090 Chain ->格雷码和二进制码的转换2182 Lost Cows ->线段树/2426 Remainder BFS1872 A Dicey Problem BFS1324 Holedox Moving BFS+压缩储存1088 滑雪DFS/DP1015 Jury Compromise DP1050 To the Max DP1062 昂贵的聘礼DP1065 Wooden Sticks DP1074 Parallel Expectations DP1093 Formatting Text DP1112 Team Them Up! DP1141 Brackets Sequence DP1157 LITTLE SHOP OF FLOWERS DP1160 Post Office DP1163 The Triangle DP1170 Shopping Offers DP1179 Polygon DP1180 Batch Scheduling DP1191 棋盘分割DP1293 Duty Free Shop DP2184 Cow Exhibition DP2193 Lenny's Lucky Lotto Lists DP2292 Optimal Keypad DP1432 Decoding Morse Sequences DP1475 Pushing Boxes DP1513 Scheduling Lectures DP1633 Gladiators DP1661 Help Jimmy DP1692 Crossed Matchings DP1712 Flying Stars DP1717 Dominoes DP1718 River Crossing DP1732 Phone numbers DP1745 Divisibility DP1771 Elevator Stopping Plan DP1776 T ask Sequences DP1874 Trade on Verweggistan DP1887 Testing the CATCHER DP1889 Package Pricing DP1946 Cow Cycling DP1187 陨石的秘密DP（BalkanOI99 Par的拓展）1485 Fast Food DP(似乎就是ioi2000的postoffice) 2385 Apple Catching DP(像NOI98“免费馅饼”) 1064 Cable master DP/二分查找1037 A decorative fence DP/组合数学1936 All in All DP?1505 Copying Books DP+二分查找1631 Bridging signals DP+二分查找1159 Palindrome DP->LCS1458 Common Subsequence DP->LCS1080 Human Gene Functions DP->LCS变形2192 Zipper DP->LCS变形1185 炮兵阵地DP->数据压缩2430 Lazy Cows DP->数据压缩1067 取石子游戏博弈论1082 Calendar Game 博弈论1085 Triangle War 博弈论1143 Number Game 博弈论2311 Cutting Game 博弈论2425 A Chess Game 博弈论1638 A number game 博弈论1694 An Old Stone Game 博弈论?1738 An old Stone Game 博弈论?1741 Tree 博弈论?2083 Fractal 递归1104 Robbery 递推1217 FOUR QUARTERS 递推1280 Game 递推2261 France '98 递推2181 Jumping Cows 递推1316 Self Numbers 递推同Humble Number一样2084 Game of Connections 递推(不必高精度) 1338 Ugly Numbers 递推(有O(n)算法)2247 Humble Numbers 递推(最优O(n)算法)1322 Chocolate 递推/组合数学1189 钉子和小球递推?1947 Rebuilding Roads 二分2418 Hardwood Species 二分查找2082 Terrible Sets 分治/1001 Exponentiation 高精度1047 Round and Round We Go 高精度1060 Modular multiplication of polynomials 高精度1131 Octal Fractions 高精度1202 Family 高精度2199 Rate of Return 高精度1646 Double Trouble 高精度1147 Binary codes 构造1148 Utopia Divided 构造2275 Flipping Pancake 构造1660 Princess FroG 构造1772 New Go Game 构造?1005 I Think I Need a Houseboat 几何1039 Pipe 几何1070 Deformed Wheel 几何1092 Farmland 几何1106 Transmitters 几何2194 Stacking Cylinders 几何2254 Globetrotter 几何2315 Football Game 几何2423 The Parallel Challenge Ballgame 几何1375 Intervals 几何1380 Equipment Box 几何1408 Fishnet 几何1514 Metal Cutting 几何1518 Problem Bee 几何1605 Horse Shoe Scoring 几何1654 Area 几何1693 Counting Rectangles 几何1774 Fold Paper Strips 几何1871 Bullet Hole 几何1875 Robot 几何1873 The Fortified Forest 几何+回溯1031 Fence 计算几何1034 The dog task 计算几何1271 Nice Milk 计算几何2284 That Nice Euler Circuit 计算几何1688 Dolphin Pool 计算几何2165 Gunman 计算几何1755 Triathlon 计算几何?1379 Run Away 计算几何->1113 Wall 计算几何->convex hull1434 Fill the Cisterns! 计算几何->离散化/1151 Atlantis 计算几何->同等安置矩形的并的面积->离散化1177 Picture 计算几何->同等安置矩形的并的周长->线段树2419 Forests 枚举2179 Inlay Cutters 枚举1025 Department 模拟1027 The Same Game 模拟1048 Follow My Logic 模拟1049 Microprocessor Simulation 模拟1073 The Willy Memorial Program 模拟1075 University Entrance Examination 模拟1098 Robots 模拟1103 Maze 模拟1120 A New Growth Industry 模拟1193 内存分配模拟1281 MANAGER 模拟2200 A Card Trick 模拟2314 POJ language 模拟1431 Calendar of Maya 模拟1483 Going in Circles on Alpha Centauri 模拟1512 Keeps Going and Going and ... 模拟1773 Outernet 模拟1876 The Letter Carrier's Rounds 模拟1883 Theseus and the Minotaur 模拟2050 Searching the Web 模拟(需要高效实现)1012 Joseph 模拟/数学方法1086 Unscrambling Images 模拟?1327 Moving Object Recognition 模拟?1893 Monitoring Wheelchair Patients 模拟+几何1462 Random Walk 模拟+解线性方程组2379 ACM Rank T able 模拟+排序1879 Tempus et mobilius Time and motion 模拟+组合数学->Polya定理1520 Scramble Sort 排序1634 Who's the boss? 排序2299 Ultra-QuickSort 排序->归并排序1008 Maya Calendar 日期处理1209 Calendar 日期处理2210 Metric Time 日期处理1430 Binary Stirling Numbers 日期处理1447 Ambiguous Dates 日期处理2080 Calendar 日期处理2351 Time Zones 时间处理1770 Special Experiment 树形DP1916 Rat Attack 数据结构->?1197 Depot 数据结构->Young T ableau1182 食物链数据结构->并查集2424 Flo's Restaurant 数据结构->堆1877 Flooded! 数据结构->堆1445 Random number 数据结构->碓1023 The Fun Number System 数论1061 青蛙的约会数论1091 跳蚤数论1152 An Easy Problem! 数论2191 Mersenne Composite Numbers 数论2381 Random Gap 数论2417 Discrete Logging 数论1510 Hares and Foxes 数论1641 Rational Approximation 数论1730 Perfect Pth Powers 数论1777 Vivian's Problem 数论2061 Pseudo-random Numbers 数论1014 Dividing 数论/DP?/组合数学->母函数?1606 Jugs 数论/搜索1995 Raising Modulo Numbers 数论->大数的幂求余2115 C Looooops 数论->解模线性方程1288 Sly Number 数论->解模线性方程组1395 Cog-Wheels 数学->解正系数的线性方程组1000 A+B Problem 送分题1003 Hangover 送分题1004 Financial Management 送分题1006 Biorhythms 送分题1007 DNA Sorting 送分题1016 Numbers That Count 送分题1019 Number Sequence 送分题1028 Web Navigation 送分题1046 Color Me Less 送分题1053 Set Me 送分题1068 Parencodings 送分题1071 Illusive Chase 送分题1096 Space Station Shielding 送分题1099 Square Ice 送分题1102 LC-Display 送分题1107 W's Cipher 送分题1119 Start Up the Startup 送分题1218 THE DRUNK JAILER 送分题1245 Programmer, Rank Thyself 送分题1247 Magnificent Meatballs 送分题1250 T anning Salon 送分题1298 The Hardest Problem Ever 送分题1326 Mileage Bank 送分题2190 ISBN 送分题2196 Specialized Four-Digit Numbers 送分题2291 Rotten Ropes 送分题2304 Combination Lock 送分题2309 BST 送分题2390 Bank Interest 送分题2403 Hay Points 送分题1411 Calling Extraterrestrial Intelligence Again 送分题1481 The Die Is Cast 送分题1484 Blowing Fuses 送分题1517 u Calculate e 送分题1547 Clay Bully 送分题1563 The Snail 送分题1604 Just the Facts 送分题1657 Distance on Chessboard 送分题1658 Eva's Problem 送分题1663 Number Steps 送分题1677 Girls' Day 送分题1690 (Your)((Term)((Project))) 送分题1775 Sum of Factorials 送分题1870 Bee Breeding 送分题2105 IP Address 送分题2136 Vertical Histogram 送分题1555 Polynomial Showdown 送分题(非常阴险) 2388 Who's in the Middle 送分题(排序)1519 Digital Roots 送分题(位数可能很大)1045 Bode Plot 送分题(用物理知识)2051 Argus 送分题(最好用堆，不用也可以过) 1011 Sticks 搜索1020 Anniversary Cake 搜索1054 The Troublesome Frog 搜索1069 The Bermuda Triangle 搜索1072 Puzzle Out 搜索1100 Dreisam Equations 搜索1110 Double Vision 搜索1111 Image Perimeters 搜索1128 Frame Stacking 搜索1142 Smith Numbers 搜索1162 Building with Blocks 搜索1183 反正切函数的应用搜索1184 聪明的打字员搜索1248 Safecracker 搜索1601 Pizza Anyone? 搜索1713 Divide et unita 搜索1129 Channel Allocation 搜索（图的最大独立集）1190 生日蛋糕搜索/DP1691 Painting A Board 搜索/DP1714 The Cave 搜索/DP1084 Square Destroyer 搜索？1010 STAMPS 搜索＋DP1194 HIDDEN CODES 搜索+DP1882 Stamps 搜索+DP1101 The Game 搜索->BFS1137 The New Villa 搜索->BFS1233 Street Crossing 搜索->BFS2243 Knight Moves 搜索->BFS2312 Battle City 搜索->BFS1476 Always On the Run 搜索->BFS1480 Optimal Programs 搜索->BFS1482 It's not a Bug, It's a Feature! 搜索->BFS 1753 Flip Game 搜索->BFS1915 Knight Moves 搜索->BFS1017 Packets 贪心1018 Communication System 贪心1323 Game Prediction 贪心1463 Strategic game 贪心1469 COURSES 贪心1719 Shooting Contest 贪心2054 Color a Tree 贪心1328 Radar Installation 贪心（差分约束系统的特例）1042 Gone Fishing 贪心/DP1752 Advertisement 贪心/图论->差分约束系统1201 Intervals 贪心/图论->最长路->差分约束系统1097 Roads Scholar 图论1161 Walls 图论1450 Gridland 图论(本来TSP问题是NP难的，但这个图比较特殊，由现成的构造方法)2197 Jill's Tour Paths 图论->2416 Return of the Jedi 图论->1639 Picnic Planning 图论->1695 Magazine Delivery 图论->1729 Jack and Jill 图论->1751 Highways 图论->1122 FDNY to the Rescue! 图论->Dijkstra1125 Stockbroker Grapevine 图论->Dijkstra1135 Domino Effect 图论->Dijkstra1394 Railroad 图论->Dijkstra1158 TRAFFIC LIGHTS 图论->Dijkstra变形2395 Out of Hay 图论->Dijkstra变形2253 Frogger 图论->Dijkstra变形(和1295是一样的)1734 Sightseeing trip 图论->Euler回路1466 Girls and Boys 图论->n/a1515 Street Directions 图论->把一个无向连通图改造成为有向强连通图1635 Subway tree systems 图论->不同表示法的二叉树判同1275 Cashier Employment 图论->差分约束系统->无负权回路的有向图的最长路->Bellman-Ford1274 The Perfect Stall 图论->二分图的最大匹配1325 Machine Schedule 图论->二分图的最大匹配2239 Selecting Courses 图论->二分图的最大匹配2195 Going Home 图论->二分图的最大权匹配2400 Supervisor, Supervisee 图论->二分图的最大权匹配?1637 Sightseeing tour 图论->欧拉回路1383 Labyrinth 图论->树的最长路1094 Sorting It All Out 图论->拓扑排序1486 Sorting Slides 图论->拓扑排序1149 PIGS 图论->网络流2289 Jamie's Contact Groups 图论->网络流?1192 最优连通子集图论->无负权回路的有向图的最长路->BellmanFord 1364 King 图论->无负权回路的有向图的最长路->BellmanFord1985 Cow Marathon 图论->有向无环图的最长路1087 A Plug for UNIX 图论->最大流1273 Drainage Ditches 图论->最大流1459 Power Network 图论->最大流1632 Vase collection 图论->最大完全图2049 Finding Nemo 图论->最短路1251 Jungle Roads 图论->最小生成树2421 Constructing Roads 图论->最小生成树1026 Cipher 组合数学1095 Trees Made to Order 组合数学2346 Lucky tickets 组合数学1286 Necklace of Beads 组合数学->Polya定理2409 Let it Bead 组合数学->Polya定理1664 放苹果组合数学->递推。

各大OJ题目归类—————————–最优化问题————————————- ———————-动态规划SOJ1162 I-KeyboardSOJ2096 Maximum SubmatrixSOJ2111 littleken bgSOJ2505 The County FairSOJ2818 QQ音速SOJ2469 Exploring PyramidsSOJ1833 Base NumbersSOJ2009 Zeros and OnesSOJ2032 The Lost HouseSOJ2289 A decorative fenceSOJ2089 lykooSOJ2440 The days in fzkSOJ2718 BookshelfSOJ2722 Treats for the Cows(二维状态，0维决策)SOJ2726 Deck of CardsSOJ2729 Space ElevatorSOJ2730 Lazy CowsSOJ2702 AlannaSOJ2713 Cut the SequenceSOJ2768 BombSOJ2779 Find the max (I) (最大M子段和问题)SOJ2796 Letter Deletion(DP基础题，最长公共子序列问题) SOJ2800 三角形SOJ2804 Longest Ordered Subsequence (II)SOJ2896 Alphacode (动态规划简单题)SOJ2930 积木城堡SOJ3037 Painting the ballsSOJ3104 Game(注意大数运算，高精度)SOJ3264 Evil GameSOJ3300 Stockholm Coins(背包问题)SOJ3360 Buying Hay(背包问题)SOJ3531 Number Pyramids(背包问题)—————-状态DPSOJ2089 lykooSOJ2819 AderSOJ2842 The TSP problemSOJ3025 Artillery(状态DP)SOJ3088 windy’s cake VIIISOJ3259 Counting numbersSOJ3262 Square Fields(二分+状态DP)SOJ3371 Mixed Up Cows—————最优化之排序(思考两个元素之间的先后关系，以此得出一个二元比较关系，并验证此关系可传递,反对称，进而排序)SOJ2509 The Milk QueueSOJ2547 cardsSOJ2850 Protecting the FlowersSOJ2957 Setting ProblemsSOJ3167 ComputerSOJ3331 Cards(2547加强版)SOJ3327 Dahema’s Computer(通过此题学会排序)—————–最优化之必要条件枚举(思考最优解所具有的性质，得出最优解的一个强必要条件，在此基础上枚举）SOJ3317 FGJ’s PlaneSOJ3429 Food portion sizes——————————–贪心—————————————SOJ1078 BlueEyes’ ScheduleSOJ1203 Pass-MurailleSOJ1673 Gone FishingSOJ2645 Buy One Get One FreeSOJ2701 In a CycleSOJ2876 Antimonotonicity(经典模型O(n)算法)SOJ3343 Tower——————————–搜索—————————————SOJ1626 squareSOJ2061 8 puzzleSOJ2485 SudokuSOJ1045 SticksSOJ2736 FliptileSOJ2771 Collecting StonesSOJ2715 Maze BreakSOJ2829 binary strings(双向BFS)SOJ3330 Windy’s Matrix(BFS)——————————–DFA—————————————-—————状态矩阵+DFA：SOJ1826 Number SequenceSOJ2552 Number of TilingsSOJ2919 Matrix Power Series (学习矩阵的快速乘法从此开始)SOJ2920 Magic BeanSOJ3021 Quad TilingSOJ3046 Odd Loving BakersSOJ3176 E-stringSOJ3246 Tiling a Grid With DominoesSOJ3323 K-Satisfied NumbersSOJ3337 Wqb’s Word—————-DFA+DPSOJ1112 Repeatless Numbers(DFA+二分)SOJ2913 Number SubstringSOJ2826 Apocalypse SomedaySOJ3030 DNA Sequence(AC自动机+矩阵二分)SOJ3128 windy和水星—水星数学家1SOJ3182 Windy numbers———————————图论———————————————————–最短路+最小生成树+强连通SOJ2832 Mars city(强连通分支，算法多多)SOJ2198 HighwaysSOJ3427 Dark roads(最小生成树，kruskal：快排+并查集)SOJ3346 Best Spot（最短路，N^3放心的写）SOJ3013 tree(树的最大—最小划分问题，二分+贪心，勉强算在图论里面吧。