Rust Function: Find maximum value

Last update on December 21 2024 10:22:10 (UTC/GMT +8 hours)

Write a Rust function that takes a vector of integers and returns the maximum value, return None if the vector is empty.

Sample Solution:

Rust Code:

fn find_max(numbers: Vec<i32>) -> Option<i32> {
    if numbers.is_empty() {
        None
    } else {
        Some(*numbers.iter().max().unwrap())
    }
}

fn main() {
    let numbers1 = vec![10, 5, 20, 15];
    let numbers2: Vec<i32> = vec![];

    match find_max(numbers1) {
        Some(max) => println!("Maximum value: {}", max),
        None => println!("The vector is empty!"),
    }

    match find_max(numbers2) {
        Some(max) => println!("Maximum value: {}", max),
        None => println!("The vector is empty!"),
    }
}

Output:

Maximum value: 20
The vector is empty!

Explanation:

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

• The 'find_max' function takes a vector of integers 'numbers'.
• If the vector is empty, it returns 'None'.
• If the vector is not empty, it uses the 'max()' method to find the maximum value and returns it as 'Some(max)'.
• In the 'main' function, we test the 'find_max' function with two vectors, one containing elements and the other empty, and print the result accordingly.

Rust Code Editor:

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