import java.util.*;

public class Main {
  public static void main (String[] args) {
    Scanner sc = new Scanner(System.in);

    long n = sc.nextLong();

    long a = (long)Math.sqrt(n);
    long ans = 0;
    for (long i = a + 1; i > 0; i--) {
      if (n % i == 0) {
        ans = i + (n / i) - 2;
        break;
      }
    }
    
    System.out.println(ans == 0 ? n - 1 : ans);
  }
}

/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