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 ans = Long.MAX_VALUE;
    for(long i=1; i < Math.sqrt(N)+1; i++){
      if(N%i==0){
        ans = Math.min((N/i)+i-2,ans);
      }
    }
    System.out.print(ans);
    return;
  }
}


/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