题目链接:http://acm.split.hdu.edu.cn/showproblem.php?pid=5391
Problem Description
Tina Town is a friendly place. People there care about each other. Tina has a ball called zball. Zball is magic. It grows larger every day. On the first day, it becomes time as large as its original size. On the second day,it will become times as large as the size on the first day. On the n-th day,it will become n times as large as the size on the (n-)-th day. Tina want to know its size on the (n-)-th day modulo n. Input
The first line of input contains an integer T, representing the number of cases. The following T lines, each line contains an integer n, according to the description.
T≤,≤n≤ Output
For each test case, output an integer representing the answer. Sample Input Sample Output
题意:求(n-1)!对n取模
方法:如果是素数就是n-1,如果不是素数(除了4)都是0,4的结果是2
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <stack>
#include <math.h>
#include <queue>
#include <vector>
using namespace std;
#define N 10010
#define ll long long
#define met(a,b) memset(a,b,sizeof(a));
vector<vector<int> >Q;
int n;
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
int f=;
scanf("%d",&n); if(n==)///特例
{
printf("2\n");
continue;
}
int k=(int)sqrt(n);
for(int i=; i<=k; i++)
{
if(n%i==)
{
f=;
break;
} } if(f)
printf("0\n");
else
printf("%d\n",n-);
}
return ;
}