#include <stdio.h>

void main(void){
	int numCount = 0 , num = 0 , ans = 0, yukiAns = 0;
	scanf("%d\n",&numCount);
	for(int i = 0 ; i < numCount ; i++){
		scanf("%d",&num);
		ans += num;
	}
	scanf("%d",&yukiAns);
	printf("%d",ans - yukiAns);
}