using System;
using System.Collections.Generic;
using static System.Console;
using System.Linq;

class abc022
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NMap(int n) => Enumerable.Repeat<int>(0, n).Select(_ => NList).ToArray();
  
    static void Main()
    {
        var n = NN;
        WriteLine((n - 1) * (n - 1));
    }
}