fn largest(list: &[i32]) -> Option<&i32> {
    let mut largest:Option<&i32> = list.get(0);

    for &item in list.iter() {
        if item > *largest.unwrap() {  //safe to unwrap here because if here 'for' detected at least 1 element which means largest is not None
            largest = Some(&item);
        }
    }

    largest
}

fn main() {
    let number_list = vec![34, 50, 25, 100, 65];

    let result = largest(&number_list);
    println!("The largest number is {:?}", result);

    let number_list = vec![102, 34, 6000, 89, 54, 2, 43, 8];

    let result = largest(&number_list);
    println!("The largest number is {:?}", result);

    let number_list = vec![];

    let result = largest(&number_list);
    println!("The largest number is {:?}", result);
}
/*
fn main() {
    let number_list:Vec<i32> = vec![];

    let mut largest:Option<&i32> = number_list.get(0);

    for number in number_list {
        if number > *largest.unwrap() {
            largest = Some(&number);
        }/*
        if number > largest {
            largest=number;
        }*/
    }

    println!("The largest number is {:?}", largest);
}*/