use proconio::{fastout, input};

#[fastout]
fn main() {
    input! {
        n: u8,
    }

    println!("{}", output(solve(n)))
}

fn solve(n: u8) -> u16 {
    ((n - 1) as u16).pow(2)
}

fn output(ans: u16) -> u16 {
    ans
}