import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long N = sc.nextLong();
		long min = Long.MAX_VALUE;

		for (int i = 1; i <= Math.sqrt(N); i++) {
			if (N %i ==0) {
				long let = i + (N/i) - 2;
				if (min > let) {
					min = let;
				}
			}
		}
		System.out.println(min);
	}

}
/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