main.rs

fn main() {
    let mut array = Array::default();
    array.push(3);
    array.push(1);
    array.push(3);
    array.push(2);
    array.push(5);
    println!("Popped: {:#?}", array.pop_max(9));
}

#[derive(Default)]
struct Array {
    items: Vec<i32>,
}

impl Array {
    pub fn push(&mut self, item: i32) {
        self.items.push(item);
    }

    // pub fn pop_max(&mut self) -> i32 {
    //     let max = self.items.iter().max().unwrap();
    //     let position = self.items.iter().position(|&i| i == *max).unwrap();
    //     self.items.remove(position)
    // }

    /// Pops parameters sent into it, returns positions of popped values
    pub fn pop_max(&mut self, mut value: i32) -> Vec<usize> {
        let mut positions = Vec::new();
        while value > 0 {
            let max = self.items.iter().max().unwrap();
            let position = self.items.iter().position(|&i| i == *max).unwrap();
            positions.push(position);
            let v = self.items.remove(position);
            value -= v;
        }
        positions
    }
}