import java.util.*;
import java.lang.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    Long N = sc.nextLong(), w=(long)Math.sqrt(N), t, min=N+1;
    for(int i=1; i<=w; i++) {
      if(N % i ==0) {
        t = i + N/i;
        if(t<min) min = t;
      }
    }
    System.out.println(min-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