import java.io.*;
import java.math.*;
import java.util.*;


public class Main {
	static int[] vy = {1,0,-1,0};
	static int[] vx = {0,1,0,-1};
	public static void main(String[] args) {	
		Scanner sc = new Scanner(System.in);
		PrintWriter out = new PrintWriter(System.out);
		int N = sc.nextInt();
		int[] A = new int[N];
		for(int i = 0; i < N; i++) {
			A[i] = sc.nextInt();
		}
		int v = sc.nextInt();
		int sum = 0;
		for(int i = 0; i < N; i++) {
			sum += A[i];
		}
		System.out.println((sum - v));
	}
}