import java.util.*;

class Main {
	Scanner sc;

	Main() {
		sc = new Scanner(System.in);
	}
	
	void calc() {
		long N = sc.nextLong();
		for (long i = (long)Math.sqrt(N); i > 0; i--) {
			if (N%i==0) {
				System.out.println(i-1+(N/i)-1);
				return;
			}
		}
	}

	public static void main(String[] args) {
		new Main().calc();
	}
}
/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