#include <iostream>
#include <fstream>

using namespace std;

int main() {
    ifstream fin("fractii.in");
    ofstream fout("fractii.out");

    int N;
    fin >> N;

    long long totalFractii = 0;

    for (int i = 1; i <= N; ++i) {
        totalFractii += N - 1;
    }

    fout << totalFractii << "\n";

    fin.close();
    fout.close();

    return 0;
}