import java.util.Scanner;
import java.lang.Math;
public class Main{

	public static void main(String[] args) {
		Scanner src=new Scanner(System.in);
		long N=src.nextLong();
		int s=(int)(Math.sqrt((double)N));
		for(int i=s;i>=1;i--) {
			if(N%i==0) {
				System.out.println(i+N/i-2);
				break;
			}
		}
		
				
		
		

	}

}
/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