题目链接: A. Memory and Crow time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows pe…

A. Memory and Crow 题目连接: http://codeforces.com/contest/712/problem/A Description There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows performing the following procedure: The crow sets ai ini…

题意:有一个序列,然后对每一个进行ai = bi - bi + 1 + bi + 2 - bi + 3.... 的操作,最后得到了a 序列,给定 a 序列,求原序列. 析:很容易看出来,bi = ai + ai+1,然后就可以得到结果了. 代码如下: #pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio> #include <string> #include <cs…

题目链接: B. Memory and Trident time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Memory is performing a walk on the two-dimensional plane, starting at the origin. He is given a string s with hi…

A. Divisibility Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/597/problem/A Description Find the number of k-divisible numbers on the segment [a, b]. In other words you need to find the number of such integer values x tha…

B. The Time 题目连接: http://www.codeforces.com/contest/622/problem/B Description You are given the current time in 24-hour format hh:mm. Find and print the time after a minutes. Note that you should find only the time after a minutes, see the examples t…

A. Infinite Sequence 题目连接: http://www.codeforces.com/contest/622/problem/A Description Consider the infinite sequence of integers: 1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5.... The sequence is built in the following way: at first the number 1 is wr…

题目链接: A. Vanya and Fence time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vanya and his friends are walking along the fence of height h and they do not want the guard to notice them. In orde…

A. Towers 题目连接: http://www.codeforces.com/contest/37/problem/A Description Little Vasya has received a young builder's kit. The kit consists of several wooden bars, the lengths of all of them are known. The bars can be put one on the top of the other…

题意:给定 n 条边,判断是不是树. 析:水题,判断是不是树,首先是有没有环,这个可以用并查集来判断,然后就是边数等于顶点数减1. 代码如下: #include <bits/stdc++.h> using namespace std; const int maxn =1000 + 5; int p[maxn]; int Find(int x){ return x == p[x] ? x : p[x] = Find(p[x]); } int main(){ int n, m, x, y; cin…