import java.util.Scanner;

// https://atcoder.jp/contests/abc144/tasks/abc144_c
public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);
		long N = sc.nextLong();
		sc.close();

		for(long i=(long) Math.sqrt(N);i>=1;i--) {
			if(N%i==0) {
				System.out.println(i+N/i-2);
				break;
			}
		}
	}
}
/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