#include

using namespace std;

int main()

{
    int N;

    double somme;

    cout << "Entrer un entier : "; cin >> N;

    if (N>=5) {

        for (int i=5; i<=N; i++) somme += i*i*i;

    }

    cout << "Somme des cubes de 5^3 a " << N << "^3 = " << somme << endl;

    cin.ignore();

    cin.get();

    return EXIT_SUCCESS;

}