import java.util.*;

public class Exercises21{
  public static void main (String[] args){

    Scanner sc = new Scanner(System.in);

    int numberOfNum = sc.nextInt();

    int[] nums = new int[numberOfNum];

    for (int n = 0; n < numberOfNum; n++){
      nums[n] = sc.nextInt();
    }

    int wrongAnswer = sc.nextInt();

    int sum = 0;

    for (int n = 0; n < numberOfNum; n++){
      sum += nums[n];
    }

    System.out.println(sum - wrongAnswer);
  }
}