#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <queue>
#include <map>
#include <cmath>
#include <iomanip>

using namespace std;

const long long MOD = (long long)(1e9) + 7;

int main() {

  //cout << fixed << setprecision(15);

  int n;
  cin >> n;
  cout << (n - 1) * (n - 1) << endl;
  return 0;
}