6335.Problem D. Nothing is Impossible 题意:给你n道题目,m个人,每题有x个正确选项,y个错误选项,问你做对题数量最多的人做对了多少道题目. 如果一道题有y个错误选项,那么我需要至少y+1个人才能保证一定有一个人做对了这道题目,所以题面上给的正确选项的数量x并没有什么实质性的作用... 假设第一题错误选项有y1个,第二题错误选项有y2个,那么怎么才能保证至少有一个人两道题目都做对了呢? 首先我需要至少y1+1个人才能保证一定有一个人做对了第一题,那么,我在做…

A simple problem Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 3702 Accepted Submission(s): 1383 Problem Description Zty很痴迷数学问题..一天,yifenfei出了个数学题想难倒他,让他回答1 / n.但Zty却回答不了^_^. 请大家编程帮助他. Input 第一行…

Problem Description There are n apples on a tree, numbered from 1 to n.Count the number of ways to pick at most m apples.   Input The first line of the input contains an integer T (1≤T≤105) denoting the number of test cases.Each test case consists of…

题意:给出一棵n个节点的树,每个节点有一个权值,Q和T玩游戏,Q先选一些不相邻的节点,T选剩下的节点,每个人的分数是所选节点的权值的异或和,权值大的胜出,问胜出的是谁. 题解: 话说,这题后面的边跟解的过程半毛钱关系没有,但是自己就是想不到,这博弈... 设sum为所有点权的异或和,A为先手得分,B为后手得分. 若sum=0,则A=B,故无论如何都是平局. 否则考虑sum二进制下最高的1所在那位,一定有奇数个点那一位为1.若先手拿走任意一个那一位为1的点,则B该位为0,故先手必胜. #inclu…

Travelling Salesman Problem Problem's Link: http://acm.hdu.edu.cn/showproblem.php?pid=5402 Mean: 现有一个n*m的迷宫,每一个格子都有一个非负整数,从迷宫的左上角(1,1)到迷宫的右下角(n,m),并且使得他走过的路径的整数之和最大,问最大和为多少以及他走的路径. analyse: 首先,因为每个格子都是非负整数,而且规定每个格子只能走一次,所以为了使和尽可能大,必定是走的格子数越多越好.这样我们就需…

River Problem Time Limit: 2000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 3947 64-bit integer IO format: %I64d      Java class name: Main The River of Bitland is now heavily polluted. To solve this problem, the King of B…

A simple Gaussian elimination problem. Time Limit: 1000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 497564-bit integer IO format: %I64d      Java class name: Main Dragon is studying math. One day, he drew a table with sev…

A simple brute force problem. Time Limit: 1000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 497164-bit integer IO format: %I64d      Java class name: Main There's a company with several projects to be done. Finish a projec…

http://poj.org/problem?id=3691 http://acm.hdu.edu.cn/showproblem.php?pid=2457 DNA repair Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 5690   Accepted: 2669 Description Biologists finally invent techniques of repairing DNA that contain…

50 years, 50 colors Problem Description On Octorber 21st, HDU 50-year-celebration, 50-color balloons floating around the campus, it's so nice, isn't it? To celebrate this meaningful day, the ACM team of HDU hold some fuuny games. Especially, there wi…