Fill a vector with random numbers c++

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You can use std::generate algorithm to fill a vector of n elements with random numbers.

In modern C++ it’s recommended not to use any time-based seeds and std::rand, but instead to use random_device to generate a seed. For software-based engine, you always need to specify the engine and distribution. Read More..

#include <random>
#include <algorithm>
#include <iterator>
#include <iostream>
#include <vector>

using namespace std;

int main()
{
    // First create an instance of an engine.
    random_device rnd_device;
    // Specify the engine and distribution.
    mt19937 mersenne_engine {rnd_device()};  // Generates random integers
    uniform_int_distribution<int> dist {1, 52};
    
    auto gen = [&dist, &mersenne_engine](){
                   return dist(mersenne_engine);
               };

    vector<int> vec(10);
    generate(begin(vec), end(vec), gen);
    
    // Optional
    for (auto i : vec) {
        cout << i << " ";
    }
    

}

If you want to rearrange the elements of a range in a random order:

  std::shuffle(begin(vec), end(vec), mersenne_engine);

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