How to create a Vector of Empty Vectors in C++ - Step by Step Examples

How to create a Vector of Empty Vectors in C++ ?

Answer

To create a vector of empty vectors in C++, you can initialize a vector and populate it with empty vectors using a for loop.

✐ Examples

1 Create Vector of Empty Vectors using for Loop

In this example,

We include the header to use the std::vector class.
We create an empty vector named empty_vector_list of type std::vector>.
We specify the number of empty vectors to create (e.g., 5).
We use a for loop to iterate a specific number of times.
Within each iteration, we add an empty vector to the vector.
The vector empty_vector_list now contains the desired number of empty vectors.

C++ Program

#include <vector>
#include <iostream>

int main() {
    std::vector<std::vector<int>> empty_vector_list;
    int num_empty_vectors = 5;

    for (int i = 0; i < num_empty_vectors; ++i) {
        empty_vector_list.push_back(std::vector<int>());
    }

    for (const auto& vec : empty_vector_list) {
        for (int val : vec) {
            std::cout << val << " ";
        }
        std::cout << std::endl;
    }

    return 0;
}

2 Create Vector of Empty Vectors using Initializer List

In this example,

We include the header to use the std::vector class.
We use the std::vector> syntax to define a vector of empty vectors and initialize it with an empty initializer list {}.
The vector empty_vector_list is automatically populated with the desired number of empty vectors.

C++ Program

#include <vector>
#include <iostream>

int main() {
    std::vector<std::vector<int>> empty_vector_list(5);

    for (const auto& vec : empty_vector_list) {
        for (int val : vec) {
            std::cout << val << " ";
        }
        std::cout << std::endl;
    }

    return 0;
}

Summary

In this tutorial, we learned How to create a Vector of Empty Vectors in C++ language with well detailed examples.

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How to create a Vector of Empty Vectors in C++ - Step by Step Examples

How to create a Vector of Empty Vectors in C++ ?

Answer

✐ Examples

1 Create Vector of Empty Vectors using for Loop

C++ Program

2 Create Vector of Empty Vectors using Initializer List

C++ Program

Summary

More C++ Vectors Tutorials