Генерация 5ти случайных неодинаковых чисел

#include "stdafx.h"
#include<stdlib.h>
#include <iostream>
 
using namespace std;
int main()
{
 
    int i, a1, a2, a3, a4, a5,sum,n;
    cout << "Enter the number of times ";
    cin >> n;
    for (i = 1; i <= n; i++) 
    {
    a1 = (rand() % 35) + 1;
    a2 = (rand() % 35) + 1;
    a3 = (rand() % 35) + 1;
    a4 = (rand() % 35) + 1;
    a5 = (rand() % 35) + 1;
    sum = a1 + a2 + a3 + a4 + a5;
    cout << a1 << " " << a2 << " " << a3 << " " << a4 << " " << a5 << " Sum= "<<sum<< endl;
    }
    system("pause");
    return 0;
}

#include <iostream>
#include <array>
#include <algorithm>
#include <thread>
#include <random>
#include <chrono>
 
int main()
{
    const unsigned count = 5;
    const unsigned all_balls = 36;
 
    std::array<unsigned, all_balls> balls;
    std::iota(balls.begin(), balls.end(), 1);
 
    std::default_random_engine gen(std::chrono::system_clock::now().time_since_epoch().count());
    std::mt19937 g(gen());
 
    std::shuffle(balls.begin(), balls.end(), g);
 
    for (unsigned i = 0; i < count; ++i)
    {
        std::this_thread::sleep_for(std::chrono::seconds(1));
        std::cout << balls[i] << " ";
    }
 
    std::cout << "\n\nGood Luck!" << std::endl;
    system("pause");
    return 0;
}