#![allow(unused)]
fn raindrops(n : u64) -> String {
    let mut rez =  String::new();
    let is_div = |factor| n % factor == 0;
    if is_div(3) { rez.push_str("Pling"); }
    if is_div(5) { rez.push_str("Plang"); }
    if is_div(7) { rez.push_str("Plong"); }
    if rez.is_empty() { rez.push_str(&n.to_string()); }
    return rez;
}
fn main() {
    println!("Raindrops(2) : {}", raindrops(2));
    println!("Raindrops(3) : {}", raindrops(3));
    println!("Raindrops(5) : {}", raindrops(5));
    println!("Raindrops(7) : {}", raindrops(7));
    println!("Raindrops(15) : {}", raindrops(15));
    println!("Raindrops(21) : {}", raindrops(21));
    println!("Raindrops(35) : {}", raindrops(35));
    println!("Raindrops(105) : {}", raindrops(105));
}