import java.util.Scanner;

class Main{
	public static void main(String[] args){
      	Scanner sc = new Scanner(System.in);
      	long x = 0, y = 0;
		long n = sc.nextLong();
      	for (long i = 1; i*i <= n; i++) { 
          if (n%i == 0) {
             x = i;     
             y = n/i;
          }
        }      
        System.out.println(x+y-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