#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define ALL(obj) (obj).begin(), (obj).end()
#define rALL(obj) (obj).rbegin(), (obj).rend()
using ll = long long;
template<class T> inline bool chmin(T& a, T b) { if ( a > b ) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if ( a < b ) { a = b; return true; } return false; }

const int INF = 1 << 30;

int main() {
    int N;
    cin >> N;
    N--;
    int ans = N*N;
    cout << ans << endl;
    return 0;
}