import java.util.*;
public class Main {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        long min = (long)999999999999.0;
        for(long i=1;i<=Math.sqrt(N);i++)  if(N%i==0&&min > (i-1)+(N/i)-1) min = (i-1)+(N/i)-1;
        System.out.println(min);
    }
}
/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