so easy 题目连接: http://acm.hdu.edu.cn/showproblem.php?pid=5650 Description Given an array with n integers, assume f(S) as the result of executing xor operation among all the elements of set S. e.g. if S={1,2,3} then f(S)=0. your task is: calculate xor…

http://acm.hdu.edu.cn/showproblem.php?pid=4565 首先知道里面那个东西,是肯定有小数的,就是说小数部分是约不走的,(因为b限定了不是一个完全平方数). 因为(a - 1)^2 < b < (a ^ 2),所以其不是完全平方数,假如是,那么设其为c,则有a - 1 < c < a,这是矛盾的 所以,向上取整这个步骤,是必不可少的了. 那么,我在它后面加上一个< 1的数,同时使得它们结合成为整数,那就相当于帮它取整了.根据二项式定理 (…

我们考虑集合中的每个数x对答案的贡献. 设集合有n个数,则包含x的子集个数有2^(n-1)个. 那么当n > 1时,x出现了偶数次,所以其对答案的贡献就是0:当 n = 1时,其对答案的贡献是 x. AC代码: #pragma comment(linker, "/STACK:1024000000,1024000000") #include<iostream> #include<cstdio> #include<cstring> #include…

n不为1的时候输出a[1],否则输出0 #include<cstdio> #include<cstring> #include<cmath> #include<queue> #include<algorithm> using namespace std; ]; int main() { int n; int T; scanf("%d",&T); while(T--) { scanf("%d",&am…

HDU 5572 An Easy Physics Problem (计算几何) 题目链接http://acm.hdu.edu.cn/showproblem.php?pid=5572 Description On an infinite smooth table, there's a big round fixed cylinder and a little ball whose volume can be ignored. Currently the ball stands still at p…

so easy  Accepts: 512  Submissions: 1601  Time Limit: 2000/1000 MS (Java/Others)  Memory Limit: 65536/65536 K (Java/Others) 问题描述 已知一个包含 nn 个元素的正整数集合 SS,设 f(S)f(S) 为集合 SS 中所有元素的异或(XOR)的结果. 如:S = \{1, 2, 3\}S={1,2,3}, 则 f(S) = 0f(S)=0. 给出集合 SS,你需要计算 将所…

So Easy! Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3804    Accepted Submission(s): 1251 Problem Description A sequence Sn is defined as: Where a, b, n, m are positive integers.┌x┐is the ce…

Problem Description A sequence Sn is defined as:Where a, b, n, m are positive integers.┌x┐is the ceil of x. For example, ┌3.14┐=4. You are to calculate Sn. You, a top coder, say: So easy!  Input There are several test cases, each test case in one lin…

Problem Description When Teddy was a child , he was always thinking about some simple math problems ,such as "What it's 1 cup of water plus 1 pile of dough .." , "100 yuan buy 100 pig" .etc.. One day Teddy met a old man in his dream ,…

题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5058 So easy Description Small W gets two files. There are n integers in each file. Small W wants to know whether these two files are same. So he invites you to write a program to check whether these two…