Define and assign a 2D array a in a single line in Rust

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I wish like define and assign a 2D array in a single line in Rust. That is, replace this excessive code with a single line, by example:

fn main() {
    println!("Sample of array 2D");

    let N = 4;
    let mut a = vec![vec![0; N]; N];
    // row 0
    a[0][0] = 00;
    a[0][1] = 10;
    a[0][2] = 35;
    a[0][3] = 30;
    // row 0
    a[1][0] = 10;
    a[1][1] = 00;
    a[1][2] = 30;
    a[1][3] = 15;
    // row 0
    a[2][0] = 35;
    a[2][1] = 30;
    a[2][2] = 05;
    a[2][3] = 30;
    // row 0
    a[3][0] = 30;
    a[3][1] = 15;
    a[3][2] = 30;
    a[3][3] = 00;

    println!("MATRIX\n{:?}", a);
}

Say, something equivalent to how I do it in C#:

int[,] a = {
    { 00, 10, 35, 30 },
    { 10, 00, 30, 15 },
    { 35, 30, 00, 30 },
    { 30, 15, 30, 00 } 
};

P.S. Excuse me if the question is too simple, I am learning Rust

rust
1 Answers

Just use nested vecs:

fn main() {
    println!("Sample of array 2D");

    let a: Vec<Vec<usize>> = vec![
        vec![00, 10, 35, 30], vec![10, 00, 30, 15], ...
    ];


    println!("MATRIX\n{:?}", a);
}

Playground

Or arrays:

let a: [[usize; 4];4] = [
    [00, 10, 35, 30], 
    [10, 00, 30, 15],
    [00, 10, 35, 30], 
    [10, 00, 30, 15]
];

Playground

user_16951720
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