D. Tricky Function Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 codeforces.com/problemset/problem/429/D Description Iahub and Sorin are the best competitive programmers in their town. However, they can't both qualify to an important contest. The sele…

A. Calculating Function Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/486/problem/A Description For a positive integer n let's define a function f: f(n) =  - 1 + 2 - 3 + .. + ( - 1)nn Your task is to calculate f(n) for a…

地址:http://codeforces.com/contest/832/problem/C 题目: C. Strange Radiation time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output n people are standing on a coordinate axis in points with positive i…

题目链接:www.codeforces.com/problemset/problem/486/A题意:求表达式f(n)的值.(f(n)的表述见题目)C++代码: #include <iostream> using namespace std; long long f(long long n) { == ) ; else - n; } int main() { long long n; cin >> n; cout << f(n) << endl; ; } C…

Calculating Function time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output For a positive integer n let's define a function f: f(n) =  - 1 + 2 - 3 + .. + ( - 1)nn Your task is to calculate f(n) f…

A. Calculating Function   For a positive integer n let's define a function f: f(n) =  - 1 + 2 - 3 + .. + ( - 1)nn Your task is to calculate f(n) for a given integer n. Input The single line contains the positive integer n (1 ≤ n ≤ 1015). Output Print…

Ayoub thinks that he is a very smart person, so he created a function f(s)f(s) , where ss is a binary string (a string which contains only symbols "0" and "1"). The function f(s)f(s) is equal to the number of substrings in the string s…

数论 Problem - B - Codeforces 题意 给定 \(n\;(1<=n<=3*10^5)\) 个数 \(a[i]\), \(1<=a[i]<=10^6\) 把 \(a[i]\) 看做是 n 个点的点权 如果 \(\frac {lcm(a[i],a[j])}{gcd(a[i],a[j])}\) 是完全平方数,则可以给 \(i\lrarr j\) 连一条无向边 每秒后都会令每个连通块中的每个点的点权变为整个连通块的点权乘积,有 \(q\;(1<=q<=3*…

题意:给你一组数,问你最少删去多少数,使得剩下的数,每个数都能整除数组中其它某个数或被数组中其它某个数整除. 题解:我们直接枚举所有因子,\(dp[i]\)表示\(i\)在数组中所含的最大因子数(当我们枚举到\(i\)时),然后用\(dp[i]\)更新以\(i\)作为因子的更大的数,注意,更新的时候\(dp[j]=max(dp[i],dp[j])\),而不是\(dp[j]+=dp[i]\),因为这样会把之前的因子重复计算. 代码: #include <bits/stdc++.h> #defin…

Codeforces Round #277 (Div. 2) A. Calculating Function time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output For a positive integer n let's define a function f: f(n) =  - 1 + 2 - 3 + .. + ( - 1)n…