import java.io.*;

public class Main {
  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    
    long n = Long.parseLong(br.readLine());
    long temp = Long.MAX_VALUE;
    for (int i=1; i<Math.sqrt(n)+10; i++){
      if (n%i == 0 && i+n/i-2 < temp) temp = i+n/i-2;
    }
    
    System.out.println(temp);
  }
}

/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