import java.util.*;

public class Main {
	public static void main(String[] args) {

		Scanner keyboard = new Scanner(System.in);

		long N = keyboard.nextLong();
		long Max = 0;
		
		for (long i = 1; i*i <= N; i++) {
			if(N%i == 0) {
				Max = i;
			} 
		}

		System.out.println(Max + N/Max -2);
		keyboard.close();
	}
}

/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