import java.util.*;
public class Main{
 public static void main(String[] args){
   Scanner sc = new Scanner(System.in);
   long N = sc.nextLong();
   long s1 = N;
   long s2 = 1;
   for(long i = (long)Math.abs(Math.sqrt(N));i>=1;i--)
   {
    	if(N%i==0) 
       	{
       	  	s1 = i;
         	s2 = N/s1;
     		break;
 		}
   }
   System.out.println(s1+s2-2);
 }
}
/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