fn main() { let mut w = input_line::()[0]; let d = input_line::()[0]; for i in 0..d - 1 { w -= w / ((d - i) * (d - i)); } println!("{}", w); } fn input_line() -> Vec { let mut s = String::new(); std::io::stdin().read_line(&mut s).ok(); s.trim() .split_whitespace() .map(|e| e.parse().ok().unwrap()) .collect() }