import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner stdIn = new Scanner(System.in);
		long n = stdIn.nextLong();
		long min = n;
		long cnt = 1;
		for (long i = 1; i < n / cnt; i++) {
			if (n % i == 0) {
				long a = i + n / i - 2;
				if (min > a) {
					min = a;
				}
			} else {
				cnt = i;
			}
		}

		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