import java.util.*;

public class Main {
    public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);
	long n = sc.nextLong();
	long min = Long.MAX_VALUE;
	for (long i=1; i<=Math.sqrt(n); i++) {
	    if (n % i == 0) {
		if (n/i + i < min) {
		    min = n/i + i;
		}
	    }
	}
	System.out.print(min-2);
    }
}

/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