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

public class pre {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		int num[] = new int[n],sum = 0;
		
		for(int i=0;i<num.length;i++){
			num[i] = s.nextInt();
			sum += num[i];
		}
		
		int y = s.nextInt();
		
		System.out.println(sum - y);
    }
}