import java.util.*;
import java.lang.Math;

public class Main {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        long n = s.nextLong();
        long l = 1;
        for (int i= 1; i <= Math.sqrt(n); i ++) {
            if (n % i == 0)
                l=i;
        }
        System.out.println(l + (n / l) - 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