import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long input = scanner.nextLong();

        long answer = input - 1;
        answer = getAnswer(input, answer);
        System.out.println(answer);
    }

    private static long getAnswer(long input, long answer) {
        int newStart = (int) Math.sqrt(input);
        for (long i = newStart; i > 1; i --) {
            if (input % i == 0) {
                long divisible = input / i;
                long possibleAnswer = (i - 1) + (divisible - 1);
                return possibleAnswer;
            }
        }
        return answer;
    }
}
/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