#include <iostream>
#include <cmath>
using namespace std;
int main()
{
int i = 1;//用于外部循环
int num1,num2; //用于计算阶乘
int sum = 1;
char ch; //用于判断是否继续计算
while(i > 0)
{
//询问用户是否继续
cout << "\n是否愿意继续(Y/N)" << endl;
cin >> ch;
if (ch == 'Y') //若为Y,开始计算
{
//计算阶乘n!
cout << "输入一个正整数,求出该数的阶乘n!" << endl;
cin >> num1;
num2 = num1;
if (num1 > 0) //计算阶乘的条件是num1>0
{
while (num1 > 0)
{
sum = sum * num1;
num1--;
}
cout << num2 << "!=" << sum << endl;
}
else //否则不计算
{
cout << "输入数字有误,请重新输入" <<