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In the previous challenge, you learned how to propagate errors using the Result<T, E> type for file handling. Rust also lets you use the ? operator to propagate Option<T> values, but instead of propagating the error it will convert the Option<T> into a None value if it is None.

This challenge focuses on propagating Option values and handling scenarios where optional values might be missing.

Your Task

Implement the function find_and_multiply:

  1. It takes three parameters:
    • A vector of integers (Vec<i32>).
    • Two indices (usize values).
  2. The function retrieves the integers at the two specified indices from the vector.
  3. If both indices are valid, it returns the product of the two integers as an Option<i32>.
  4. If any index is out of bounds, the function returns None.
  5. Use the ? operator to propagate None values.
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pub fn find_and_multiply(numbers: Vec<i32>, index1: usize, index2: usize) -> Option<i32> {
    // TODO: Instead of using `unwrap`, use the `?` operator to propagate the option
    // HINT: `numbers.get` returns a Option<i32> value


    let num1 = numbers.get(index1).unwrap();
    let num2 = numbers.get(index2).unwrap();
    Some(num1 * num2)
}


// Example usage
pub fn main() {
    let numbers = vec![1, 2, 3, 4, 5];


    // Example 1: Both indices are valid
    let result = find_and_multiply(numbers.clone(), 1, 3);
    println!("{:?}", result); // Should print Some(8)


    // Example 2: One index is out of bounds
    let result = find_and_multiply(numbers.clone(), 1, 10);
    println!("{:?}", result); // Should print None
}