程序：n的阶乘求法

#include <stdio.h>

int main()

{

  int i = 1;

  int n = 0;

  scanf("%d", &n);

  int r = 1;

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

  {

  r = i * r;

  }

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

  return 0;

}