import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		// 整数の入力
		long a = sc.nextLong();
		// スペース区切りの整数の入力
		long b = (long)Math.pow(a, 0.5);
		// 文字列の入力
		for(long i = b; i > 0; i--){
			if(a % i == 0){
				System.out.println(i + a / 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