组合数

最新推荐文章于 2024-11-01 11:00:49 发布

qzshiyongjie

最新推荐文章于 2024-11-01 11:00:49 发布

阅读量386

点赞数

CC 4.0 BY-SA版权

文章标签： include

本文链接：https://blog.youkuaiyun.com/qzshiyongjie123/article/details/7307782

#include <iostream>
using namespace std;
long fac (int n)
{
	int sum=1,i=1;
	for (i=1;i<=n;i++)
		sum=sum*i;
	return sum;
}
long fac (int n,int m)
{
	int sum=1,i=1;
	for (i=1 ;i<=(m-n);i++)
		sum=sum*i;
	return sum;
}
int main ()
{
	int m,n,a;
	cin>>n>>m;
	a=fac(n)*fac(n,m);
	cout<<fac(m)/a;
	return 0;
}