import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        
        Scanner sc = new Scanner(System.in);
        
        long n = Long.parseLong(sc.next());
        
        long x = n;
        for(int i = 1; i <= Math.sqrt(n); i++){
            if(n%i == 0){
                x = i;
            }
        }
        
        System.out.println(x + n/x -2);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz