Rust Array Search Guide

Last update on December 21 2024 10:21:31 (UTC/GMT +8 hours)

Write a Rust program to create an array of integers with size 7 and initialize it with random values. Search for a specific value in the array and print whether it exists or not.

Sample Solution:

Rust Code:

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

fn main() {
    // Define an array with a size of 7 and initialize it with random values
    let mut arr: [i32; 7] = [0; 7]; // Declare an array of type i32 (integer) with a size of 7 and initialize it with zeros
    let mut rng = rand::thread_rng(); // Initialize the random number generator
    
    for i in 0..7 { // Iterate over each index of the array
        arr[i] = rng.gen_range(1..101); // Generate a random integer between 1 and 100 and assign it to the current index
    }

    // Define the value to search for
    let search_value = 50;

    // Search for the value in the array
    let exists = arr.iter().any(|&x| x == search_value); // Use the any() method on an iterator over the array elements to check if any element matches the search value

    // Print whether the value exists in the array or not
    if exists {
        println!("The value {} exists in the array.", search_value); // Print a message indicating that the value exists
    } else {
        println!("The value {} does not exist in the array.", search_value); // Print a message indicating that the value does not exist
    }
}

Output:

The value 50 does not exist in the array.

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 arr: [i32; 7] = [0; 7];: This line declares an array named 'arr' of type i32 (integer) with a size of 7 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..7 { ... }: This line starts a for loop that iterates over each index of the array arr.
• arr[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 'arr'.
• let search_value = 50;: This line defines the value to search for in the array.
• let exists = arr.iter().any(|&x| x == search_value);: This line uses the "any()" method on an iterator over the array elements to check if any element matches the search value "search_value".
• if exists { ... } else { ... }: This line starts a conditional statement to print whether the value exists in the array or not, based on the value of the 'exists' variable. If 'exists' is 'true', it prints a message indicating that the value exists; otherwise, it prints a message indicating that the value does not exist.

Rust Code Editor:

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