#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,j;
	cin>>n;
	for(int i=1;i<=n;i++){
		j=n*n;
	}
	cout<<j-3;
} 
/**************************************************************
	Problem: 1689
	User: huxuanchen
	Language: C++
	Result: Wrong Answer
****************************************************************/