#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

int main()
{
	int n = 0;
	int num = 0;
	int total = 0;
	int yukiAns = 0;

	scanf("%d", &n);

	for (int i = 0;i < num;i++)
	{
		int tmp = 0;
		scanf("%d", &tmp);
		total += tmp;
	}
	
	scanf("%d", &yukiAns);
	
	printf("%d", total - yukiAns);

	return 0;
}