Rust Array Reversal Guide

Last update on December 21 2024 10:19:11 (UTC/GMT +8 hours)

Write a Rust program to create an array of characters with size 7 and initialize it with random characters. Reverse the elements of the array and print the reversed array.

Sample Solution:

Rust Code:

use rand::distributions::Alphanumeric;
use rand::{thread_rng, Rng};

fn main() {
    let mut arr: [char; 7] = ['a'; 7];
    let mut rng = thread_rng();

    for i in 0..7 {
        // Generate a random alphanumeric character and convert it to char
        arr[i] = rng.sample(Alphanumeric) as char;
    }

    arr.reverse();

    println!("Reversed Array: {:?}", arr);
}

Output:

Reversed Array: ['Z', 'Q', 'Y', 'o', 'X', 't', '9']

Explanation:

Here is a brief explanation of the above Rust code:

• use rand::distributions::Alphanumeric;: This line imports the "Alphanumeric" distribution from the rand::distributions module. This distribution is used for generating random alphanumeric characters.
• use rand::{thread_rng, Rng};: This line imports the "thread_rng()" function and the 'Rng' trait from the 'rand' crate. "thread_rng()" function creates a thread-local random number generator, and 'Rng' trait provides methods for generating random numbers.
• fn main() { ... }: This line defines the main function, which serves as the entry point of the Rust program.
• let mut arr: [char; 7] = ['a'; 7];: This line declares an array named 'arr' of type 'char' (character) with a size of 7 and initializes all elements with the character 'a'.
• let mut rng = thread_rng();: This line initializes the random number generator by creating a thread-local generator using the "thread_rng()" function.
• for i in 0..7 { ... }: This line starts a for loop that iterates over each index of the array 'arr'.
• arr[i] = rng.sample(Alphanumeric) as char;: This line generates a random alphanumeric character using the "sample()" method with the "Alphanumeric" distribution, then converts it to a 'char' type and assigns it to the current index i of the array 'arr'.
• arr.reverse();: This line reverses the order of elements in the array 'arr'.
• println!("Reversed Array: {:?}", arr);: This line prints the reversed array 'arr' to the console using debug formatting.

Rust Code Editor:

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