Rust Vector sorting & slicing

Rust Vectors, Arrays, and Slices: Exercise-3 with Solution

Witre a Rust program that creates a vector of random integers. Sort the vector in ascending order and slice it to get a sub-vector containing the top 3 elements. Print the sub-vector.

Sample Solution:

Rust Code:

use rand::prelude::*; // Import the necessary traits for random number generation

fn main() {
    // Create a vector to store random integers
    let mut numbers: Vec = Vec::new(); // Declare an empty vector to store integers

    // Initialize the random number generator
    let mut rng = thread_rng(); // Create a random number generator instance

    // Generate random integers and add them to the vector
    for _ in 0..10 {
        // Generate a random integer between 1 and 100
        let num = rng.gen_range(1..=100); // Use the gen_range method to generate random numbers within a range
        numbers.push(num); // Add the generated number to the vector
    }

    // Sort the vector in ascending order
    numbers.sort(); // Use the sort method to sort the vector

    // Slice the vector to get a sub-vector containing the top 3 elements
    let top_three = &numbers[numbers.len() - 3..]; // Slice the vector from the third last element to the end

    // Print the sub-vector containing the top 3 elements
    println!("Top three elements: {:?}", top_three); // Print the sub-vector using debug formatting
}

Output:

Top three elements: [70, 91, 92]

Explanation:

Here is a brief explanation of the above Rust code:

• use rand::prelude::*;: This line imports the necessary traits for random number generation from the 'rand' crate.
• fn main() { ... }: This line defines the main function, which is the entry point of the Rust program.
• let mut numbers: Vec<i32> = Vec::new();: This line declares an empty vector named numbers to store integers.
• let mut rng = thread_rng();: This line creates an instance of the random number generator.
• for _ in 0..10 { ... }: This line starts a loop to generate 10 random integers.
• let num = rng.gen_range(1..=100);: This line generates a random integer between 1 and 100 using the "gen_range()" method.
• numbers.push(num);: This line adds the generated random number to the vector numbers.
• numbers.sort();: This line sorts the vector 'numbers' in ascending order using the sort method.
• let top_three = &numbers[numbers.len() - 3..];: This line slices the vector to get a sub-vector containing the top 3 elements.
• println!("Top three elements: {:?}", top_three);: This line prints the sub-vector containing the top 3 elements using debug formatting.

Rust Code Editor:

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