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

How to create a Vector of Empty Vectors in Rust ?

Answer

To create a vector of empty vectors in Rust, 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 create an empty vector named empty_vector_list.
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.

Rust Program

fn main() {
    let mut empty_vector_list: Vec<Vec<i32>> = Vec::new();
    let num_empty_vectors = 5;

    for _ in 0..num_empty_vectors {
        empty_vector_list.push(Vec::new());
    }

    println!("{:?}", empty_vector_list);
}

Output

[[], [], [], [], []]

2 Create Vector of Empty Vectors using vec! Macro

In this example,

We use the vec! macro followed by square brackets [] to create a vector of empty vectors.
Inside the square brackets, we specify the number of empty vectors to create.
The vec! macro generates a vector with the specified number of empty vectors.

Rust Program

fn main() {
    let num_empty_vectors = 5;
    let empty_vector_list = vec![Vec::new(); num_empty_vectors];

    println!("{:?}", empty_vector_list);
}

Output

[[], [], [], [], []]

Summary

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

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

How to create a Vector of Empty Vectors in Rust ?

Answer

✐ Examples

1 Create Vector of Empty Vectors using for Loop

Rust Program

Output

2 Create Vector of Empty Vectors using vec! Macro

Rust Program

Output

Summary

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