fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();

    let mut result = n;
    for j in 2.. {
        let i = ((n as f64).powf(1. / j as f64) + 1e-10).floor() as usize;
        if i == 1 { break; }
        let k = n - i.pow(j);
        result = result.min(i + j as usize + k);
    }
    println!("{}", result);
}