利用函数求阶乘

#include <stdio.h>#include <stdlib.h>int main (){int fac(int n);int n;int y;scanf("%d",&n);y=fac(n);printf("%d!=%d\n",n,y);system ("pause");return 0;}int fac(int n){int f;if(n<0)printf("data error!");else if (n==0||n==1)f=1;else f=fac(n-1)*n;return (f);}

注意递归方法的使用！