import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No369 {

	public static void main(String[] args) {
		try{
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			int N = Integer.parseInt(br.readLine());
			String[] str = br.readLine().split(" ");
			int[] num = new int[N];
			int sum =0;
			for(int i=0; i < N; i++){
				num[i] = Integer.parseInt(str[i]);
				sum += num[i];
			}
			int v = Integer.parseInt(br.readLine());
			System.out.println(sum - v);
			
		}catch(IOException e){
			e.getStackTrace();
		}catch(NumberFormatException e){
			e.getStackTrace();
		}
	}
}