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 = n-1;

		for(long i =1; i * i <= n;i++) {
			if(n % i != 0) {
				continue;
			}else {
				if(min > i + n/i -2) {
					min = i + n/i -2;
				}
			}
		}
		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