1083. Factorials!!!
Time limit: 1.0 secondMemory limit: 64 MB
Definition 1. n!!…! = n(nk)(n2k)…(n mod k), ifk doesn’t divide n; n!!…! = n(nk)(n2k)…k, ifk divides n (There are k marks ! in the both cases).
Definition 2.X mod Y — a remainder after division of X by Y.
For example, 10 mod 3 = 1; 3! = 3·2·1; 10!!! = 10·7·4·1.
Given numbers n and k we have calculated a value of the expression in the first definition. Can you do it as well?
Input
contains the only line: one integer n, 1 ≤n ≤ 10, then exactly one space, then k exclamation marks, 1 ≤ k ≤ 20.
Output
contains one number — n!!…! (there are k marks ! here).
Sample
inputoutput
9 !!945
Problem Author: Oleg KatzProblem Source: The 3rd high school children programming contest, USU, Yekaterinburg, Russia, March 4, 2001
解析：直接按题目中的定义计算即可。
AC代码：
#include <bits/stdc++.h>using namespace std;int main(){int n;string s;while(~scanf("%d", &n)){cin>>s;int k = s.size();int ans = 1;if(n % k){int t = n / k;for(int i=0; i<=t; i++){ans *= (n – i * k);}}else{int t = n / k – 1;for(int i=0; i<=t; i++){ans *= (n – i * k);}}printf("%d\n", ans);}return 0;}
，将会错过更好的风景，保持一份平和，保持一份清醒。
