求阶乘 输入一个正整数 n 输出n！

#include<stdio.h>

int factorial (int n);

int main(){

int n;

scanf("%d",&n);

printf("%d \n",factorial(n));

return 0;

}

int factorial(int n){

int i,fact=1;

for(i=1;i<=n;i++)

fact = fact*i;

return fact;

}