Rust Array Concatenation Guide

Rust Arrays: Exercise-9 with Solution

Write a Rust program to create two arrays of integers, each with size 4, and initialize them with random values. Concatenate the two arrays and print the resulting array.

Sample Solution:

Rust Code:

use rand::Rng; // Import the rand crate to generate random numbers

fn main() {
    // Define an array with a size of 4 and initialize it with random values
    let mut arr1: [i32; 4] = [0; 4]; // Declare an array of type i32 (integer) with a size of 4 and initialize it with zeros
    let mut rng = rand::thread_rng(); // Initialize the random number generator
    
    for i in 0..4 { // Iterate over each index of the array
        arr1[i] = rng.gen_range(1..101); // Generate a random integer between 1 and 100 and assign it to the current index
    }

    // Define another array with a size of 4 and initialize it with random values
    let mut arr2: [i32; 4] = [0; 4]; // Declare another array of type i32 (integer) with a size of 4 and initialize it with zeros
    
    for i in 0..4 { // Iterate over each index of the array
        arr2[i] = rng.gen_range(1..101); // Generate a random integer between 1 and 100 and assign it to the current index
    }

    // Concatenate the two arrays
    let mut concatenated_array: [i32; 8] = [0; 8]; // Declare a new array with a size of 8 to hold the concatenated values
    
    for i in 0..4 { // Iterate over each index of the arrays
        concatenated_array[i] = arr1[i]; // Copy elements from the first array to the concatenated array
        concatenated_array[i + 4] = arr2[i]; // Copy elements from the second array to the concatenated array, starting from index 4
    }

    // Print the resulting concatenated array
    println!("Concatenated Array: {:?}", concatenated_array); // Print the resulting concatenated array using debug formatting
}

Output:

Concatenated Array: [33, 24, 93, 74, 77, 81, 33, 15]

Explanation:

Here is a brief explanation of the above Rust code:

• use rand::Rng;: This line imports the rand::Rng trait from the "rand" crate, which provides functions for generating random numbers.
• fn main() {: This line defines the main function, which is the entry point of the Rust program.
• let mut arr1: [i32; 4] = [0; 4];: This line declares an array named 'arr1' of type 'i32' (integer) with a size of 4 and initializes it with zeros.
• let mut rng = rand::thread_rng();: This line initializes the random number generator by creating a thread-local generator.
• for i in 0..4 { ... }: This line starts a for loop that iterates over each index of the array arr1.
• arr1[i] = rng.gen_range(1..101);: This line generates a random integer between 1 and 100 using the gen_range method of the random number generator 'rng', and assigns it to the current index 'i' of the array 'arr1'.
• Similarly, let mut arr2: [i32; 4] = [0; 4]; and the subsequent loop initializes 'arr2' with random values.
• let mut concatenated_array: [i32; 8] = [0; 8];: This line declares a new array named concatenated_array of type 'i32' (integer) with a size of 8 to hold the concatenated values.
• The next loop copies elements from 'arr1' and 'arr2' into concatenated_array, ensuring that elements from 'arr2' are placed after the elements from 'arr1'.
• Finally, println!("Concatenated Array: {:?}", concatenated_array); prints the resulting concatenated array to the console using debug formatting.

Rust Code Editor:

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