View Code of Problem 610

#include <cstdio>
#include <iostream>
using namespace std;
long long f(int m,int n){
	long long ans=1;
	for(int i=1;i<=n;i++){
		ans=ans*m/i;
		m--;
	}
	return ans;

}
int main(){
	int n;
	while(scanf("%d",&n)!=EOF){
			printf("%Ld\n",f(n*2,n)/(n+1));
	}

}


/*
10 5

10 10 5 5 


10 10 5 10 5 5
10 10 10 5 5 5

10 10 10 5 10 5 5 5
10 10 10 5 5 10 5 5
10 10 10 10 5 5 5 5


10 10 10 10 5 10 5 5 5 5 
10 10 10 10 5 5 10 5 5 5 
10 10 10 10 5 5 5 10 5 5
10 10 10 10 10 5 5 5 5 5

*/