import java.util.Scanner;

class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long N = sc.nextLong();
    int x = (int)Math.sqrt((double)N);
    
    for(; x>1; x--){
      if(N % x == 0){
        break;
      }
    }
    
    System.out.println(x - 1 + N/x - 1);
  }
}

/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