#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int main(void){
int n,v,a[10005];
scanf("%d",&n);
int sum=0;
for(int i=0;i<n;i++){
    scanf("%d",&a[i]);
    sum=sum+a[i];
}
scanf("%d",&v);
printf("%d\n",sum-v);

}