import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long N = sc.nextLong();
        long f = (long) Math.ceil(Math.sqrt(N));
        long min = N - 1;
        for (long i = 1; i <= f; i++) {
            if (N % i != 0) {
                continue;
            }
            if (N / i + i - 2 <= min) {
                min = N / i + 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