A. Rounding   time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasya has a non-negative integer n. He wants to round it to nearest integer, which ends up with 0. If n already ends up with …

简单题. 删去结尾的不是$0$的数字,保证结尾连续的$k$个都是$0$,如果不能做到,就保留一个$0$. #include<map> #include<set> #include<ctime> #include<cmath> #include<queue> #include<string> #include<vector> #include<cstdio> #include<cstring> #in…

C. Phone Numbers   time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Vasya has several phone books, in which he recorded the telephone numbers of his friends. Each of his friends can have on…

B. Proper Nutrition   time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasya has n burles. One bottle of Ber-Cola costs a burles and one Bars bar costs b burles. He can buy any non-negative…

Proper Nutrition 题意:有n元钱,有2种单价不同的商品,是否存在一种购买方式使得钱恰好花光,如果有输入任意一种方式,如果没有输出“NO” 题解:可以使用拓展欧几里得快速求解. #include<iostream> using namespace std; #define ll long long ll gcd(ll a, ll b) { return b? gcd(b, a%b) : a; } void ex_gcd(ll a, ll b, ll &x, ll &…

A /* Huyyt */ #include <bits/stdc++.h> #define mem(a,b) memset(a,b,sizeof(a)) #define mkp(a,b) make_pair(a,b) #define pb push_back ][] = {{, }, {, }, {, -}, { -, }, {, }, {, -}, { -, -}, { -, }}; using namespace std; typedef long long ll; int main()…

目录 Codeforces #402 Codeforces #402 Codeforces 779A Pupils Redistribution 链接:http://codeforces.com/contest/779/problem/A 题意:有A组和B组,每组有n个人,A组里面每个人的分值为\(a_i\),B组里面每个人的分值为\(b_i\),\(1\le a_i ,b_i\le5\),至少双方要交换多少人才能使使A组里面每种分值的人要和B组里面一样多. 思路:如果两个在\(i\)这个分值上…

http://codeforces.com/problemset/problem/351/A 题意: 2*n个数,选n个数上取整,n个数下取整 最小化 abs(取整之后数的和-原来数的和) 先使所有的数都下取整,累积更改的sum 那么选1个小数上取整,就会使sum-1 整数上下取整不会产生影响 所以有1个整数就可以使上取整的小数少1个 所以ans=min(abs(i-sum)) i∈[n-整数个数,n] #include<cmath> #include<cstdio> #inclu…

C. Jeff and Rounding time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Jeff got 2n real numbers a1, a2, ..., a2n as a birthday present. The boy hates non-integer numbers, so he decided to sli…

C. Jeff and Rounding time limit per test:  1 second memory limit per test: 256 megabytes input: standard input output: standard output Jeff got 2n real numbers a1, a2, ..., a2n as a birthday present. The boy hates non-integer numbers, so he decided t…