#include <stdio.h>
int main(){
    //input
    int N;
    scanf("%d",&N);

    int total = 0;
    for (int i = 0;i < N;i++){
        int A;
        scanf("%d",&A);
        total += A;
    }

    int v;
    scanf("%d",&v);

    //output
    printf("%d\n",total-v);
    return 0;
}