The Maths Lecture 题意:求存在后缀Si mod k =0,的n位数的数目.(n <=1000,k<=100); 用f[i][j]代表 长为i位,模k等于j的数的个数. 可以用 f[i+1][(t*10i+j)%k]=∑f[i][j]+(j==0),(t*10i+j)%k!=0;动态规划 这样可以求出所有f[n][i] i>0 的值. 最后用9*10^(n-1)-∑f[n][i] 就可以得到 答案 #include <bits/stdc++.h> using…

传送门 D. The Maths Lecture time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr doesn't like Maths as he finds it really boring, so he usually sleeps in Maths lectures. But one day the teacher…

题目链接:http://www.codeforces.com/problemset/problem/339/A题意:重新组合加法字符串,使得按照1,2,3的顺序进行排列.C++代码: #include <iostream> #include <string> using namespace std; ]; string s, ans = ""; int main() { cin >> s; int len = s.length(); ; i <…

题目链接: http://codeforces.com/problemset/problem/507/E E. Breaking Good time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Breaking Good is a new video game which a lot of gamers want to have. There is a certain level in the game that…

题目传送门 /* 贪心水题 */ #include <cstdio> #include <algorithm> #include <iostream> #include <cmath> #include <cstring> #include <vector> #include <set> #include <map> #include <string> using namespace std; ;…

C. Guess Your Way Out! time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr bought a new video game "Guess Your Way Out!". The goal of the game is to find an exit from the maze that loo…

A. Amr and Music (贪心) 水题,没能秒切,略尴尬. #include <cstdio> #include <algorithm> using namespace std; +; int a[maxn], r[maxn], ans[maxn]; int cmp(int i, int j) { return a[i] < a[j]; } int main() { //freopen("in.txt", "r", stdin…

C. Guess Your Way Out! time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr bought a new video game "Guess Your Way Out!". The goal of the game is to find an exit from the maze that loo…

B. Amr and Pins time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr loves Geometry. One day he came up with a very interesting problem. Amr has a circle of radius r and center in point (x, …

A. Amr and Music time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr is a young coder who likes music a lot. He always wanted to learn how to play music but he was busy coding so he got an…