BillDivision.java

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class BillDivision {

    // Complete the bonAppetit function below.
    static void bonAppetit(List<Integer> bill, int k, int b) {
      int sum = 0;
      for(int i=0;i<bill.size();i++){
         if(i != k){
           sum += bill.get(i);
         }  
      }
      if(sum/2 == b){
         System.out.println("Bon Appetit");
      }else{
        System.out.println(Math.abs(sum/2 - b));
      }

    }

    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

        String[] nk = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");

        int n = Integer.parseInt(nk[0]);

        int k = Integer.parseInt(nk[1]);

        String[] billItems = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");

        List<Integer> bill = new ArrayList<>();

        for (int i = 0; i < n; i++) {
            int billItem = Integer.parseInt(billItems[i]);
            bill.add(billItem);
        }

        int b = Integer.parseInt(bufferedReader.readLine().trim());

        bonAppetit(bill, k, b);

        bufferedReader.close();
    }
}