Rust Program: Find maximum and minimum in array

Rust Functions and Control Flow: Exercise-3 with Solution

Write a Rust program that implements two functions to find the maximum and minimum numbers in an array.

Sample Solution:

Rust Code:

fn find_max(numbers: &[i32]) -> Option<i32> {
    // Return None if the array is empty
    if numbers.is_empty() {
        return None;
    }

    // Initialize max_num with the first element of the array
    let mut max_num = numbers[0];

    // Iterate over the array to find the maximum number
    for &num in numbers {
        if num > max_num {
            max_num = num;
        }
    }

    Some(max_num)
}

fn find_min(numbers: &[i32]) -> Option<i32> {
    // Return None if the array is empty
    if numbers.is_empty() {
        return None;
    }

    // Initialize min_num with the first element of the array
    let mut min_num = numbers[0];

    // Iterate over the array to find the minimum number
    for &num in numbers {
        if num < min_num {
            min_num = num;
        }
    }

    Some(min_num)
}

fn main() {
    let numbers = [3, 7, 2, 8, 1, 5]; // Define an array of numbers

    // Call the find_max function to find the maximum number
    match find_max(&numbers) {
        Some(max) => println!("Maximum number: {}", max),
        None => println!("The array is empty!"),
    }

    // Call the find_min function to find the minimum number
    match find_min(&numbers) {
        Some(min) => println!("Minimum number: {}", min),
        None => println!("The array is empty!"),
    }
}

Output:

Maximum number: 8
Minimum number: 1

Explanation:

Here's a brief explanation of the above Rust code:

• 'find_max' function: This function takes a slice of 'i32' numbers as input and returns an 'Option<i32>' representing the maximum number found in the array. If the array is empty, it returns 'None'. Otherwise, it iterates over the array to find the maximum number.
• 'find_min' function: This function takes a slice of 'i32' numbers as input and returns an 'Option<i32>' representing the minimum number found in the array. If the array is empty, it returns 'None'. Otherwise, it iterates over the array to find the minimum number.
• 'main' function: In the 'main' function, we define an array of numbers. We then call the 'find_max' function to find the maximum number and the 'find_min' function to find the minimum number in the array. Finally, we print the results.

Rust Code Editor:

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