import java.util.Scanner;

class Main {

	static Scanner sc = new Scanner(System.in);

	public static void main(String[] args) {
		long N = sc.nextLong(),
				x = 1,
				y = 1,
				max_p=2;
		boolean f=false;
		for(int i=1;i<=(long)Math.pow(N, 0.5);i++) {
			if(N%i==0) {
				max_p = i;
				f=true;
			}
		}
		x=max_p-1;
		y=N/max_p-1;
		System.out.println(f?x+y:N-1);
	}
}
/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