import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long N = sc.nextLong();
		sc.close();

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