use std::io;
    fn main(){
        let mut input = String::new();
        io::stdin().read_line(&mut input).expect("Failed to read line");
        let n: usize = input.trim().parse().expect("Input is not an integer");
        
        if n == 3 {
            println!("5");
        }else{
     
        for i in 0..100 {
            let odd = 2*i+1;
            let acc = (odd/2)*odd + (odd/2) + 1;
            if n <= acc{
                println!("{odd}");
                break;
            }
        }
        }
    }