[codeforces 509]C. Sums of Digits 试题描述 Vasya had a strictly increasing sequence of positive integers a1, ..., an. Vasya used it to build a new sequence b1, ..., bn, where bi is the sum of digits of ai's decimal representation. Then sequence ai got lo…
[codeforces 55]D. Beautiful numbers 试题描述 Volodya is an odd boy and his taste is strange as well. It seems to him that a positive integer number is beautiful if and only if it is divisible by each of its nonzero digits. We will not argue with this and…
D. Restoring Numbers Vasya had two arrays consisting of non-negative integers: a of size n and b of size m. Vasya chose a positive integerk and created an n × m matrix v …
D. Artsem and Saunders 题目连接: http://codeforces.com/contest/765/problem/D Description Artsem has a friend Saunders from University of Chicago. Saunders presented him with the following problem. Let [n] denote the set {1, ..., n}. We will also write f:…
A. Plus and Square Root time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output ZS the Coder is playing a game. There is a number displayed on the screen and there are two buttons, ' + ' (plus) an…
题意:给定两个数 m,n,问你在从1到 n,和从 1到 m中任选两个数加起来是5的倍数,问你有多少个. 析:先计算 m 和 n中有多少个取模5是从0到4的,然后根据排列组合,相乘就得到了小于等于 m 和 n的并且能整除五的个数,然后再加上剩下的. 代码如下: #include <bits/stdc++.h> using namespace std; typedef long long LL; const int aa = 1234567; const int bb = 123456; cons…
