import java.util.*;

class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long N = Long.parseLong(sc.next());
    long M = (int)Math.sqrt(N);
    long Re = N+1;
    for(int i = 0;i<M;i++){
      if(N%(M-i)==0&&Re>M-i+N/(M-i)){
        Re = M-i+N/(M-i);
      }
    }
    System.out.println(Re-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