import java.util.*;

public class Main { 
    public static void main(String[] args) {
      Scanner sc=new Scanner(System.in);
      long n=sc.nextLong();
      long o;
      long x=Long.MAX_VALUE/2;
      long y=Long.MAX_VALUE/2;
      long r=(long)Math.sqrt(n);
      for(long i=1;i<=r;i++){ 
      	if(n%i==0){
        	long j=n/i;
            if ((i+j)<(x+y)){
            	x=i;
                y=j;
            }
        }
      }
      o=x+y-2;
      System.out.println(o);
    }
}
/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