How to get a Random Item in a Set in C++

How to get a Random Item in a Set in C++ ?

Answer

To retrieve a random item from a set in C++, you can utilize the `std::vector` container along with the `std::random_device` and `std::uniform_int_distribution` classes.

✐ Examples

1 Get Random Item from Set

In this example,

We include necessary header files such as `iostream`, `vector`, `random`, and `ctime`.
We create a vector named `my_set` and populate it with elements.
We seed the random number generator using `std::random_device` combined with `std::mt19937` engine.
We use `std::uniform_int_distribution` to generate a random index within the size of the set.
We access the element at the randomly generated index to retrieve the random item.
Finally, we print the randomly selected item.

C++ Program

#include <iostream>
#include <vector>
#include <random>
#include <ctime>

int main() {
    // Create and populate the set (vector)
    std::vector<int> my_set = {1, 2, 3, 4, 5};

    // Seed the random number generator
    std::random_device rd;
    std::mt19937 gen(rd());

    // Generate random index
    std::uniform_int_distribution<> dis(0, my_set.size() - 1);
    int random_index = dis(gen);

    // Get random item from set
    int random_item = my_set[random_index];

    // Print random item
    std::cout << "Random item from set: " << random_item << std::endl;
    return 0;
}

Output

Random item from set: [random value]

Summary

In this tutorial, we learned How to get a Random Item in a Set in C++ language with well detailed examples.

◀ Previous Next ▶

C++ Tutorials

C++ How-Tos