#include <stdio.h>

int main()
{
	int n;
	int sum = 0;
	int i;
	int wrong;
	
	scanf("%d",&n);
	for (i=0;i<n;i++){
		int num;
		scanf("%d",&num);
		sum += num;
	}
	
	scanf("%d",&wrong);
	
	printf("%d",(sum-wrong));

}