Exercise: Nested Arrays

Arrays can contain other arrays:

// Copyright 2023 Google LLC
// SPDX-License-Identifier: Apache-2.0

let array = [[1, 2, 3], [4, 5, 6], [7, 8, 9]];

What is the type of this variable?

Use an array such as the above to write a function transpose that transposes a matrix (turns rows into columns):

Copy the code below to https://play.rust-lang.org/ and implement the function. This function only operates on 3×3 matrices.

// Copyright 2023 Google LLC
// SPDX-License-Identifier: Apache-2.0

fn transpose(matrix: [[i32; 3]; 3]) -> [[i32; 3]; 3] {
    todo!()
}

fn main() {
    let matrix = [
        [101, 102, 103], // <-- the comment makes rustfmt add a newline
        [201, 202, 203],
        [301, 302, 303],
    ];

    println!("Original:");
    for row in matrix {
        println!("{row:?}");
    }

    let transposed = transpose(matrix);

    println!("\nTransposed:");
    for row in transposed {
        println!("{row:?}");
    }
}