#include <iostream>
#include <cassert>
long long gcd(long long a, long long b){
	return (b?gcd(b,a%b):a);
}

int main(){
	long long n;
	std::cin >> n;
	assert(1<=n && n<=1000000000);
	std::cout << gcd(n,n*(n-1)/2) << std::endl;
}