#include <bits/stdc++.h>
using namespace std;

//--------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define RFOR(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define LL long long
#define INF INT_MAX/3

//--------------------------------------------
const double EPS = 1e-14;
const double PI  = acos(-1.0);

//--------------------------------------------

int main(){
  int n, a;
  int v;
  int sum = 0;
  
  scanf("%d",&n);
  REP (i, n) {
    scanf("%d",&a);
    sum = sum + a;
  }
  scanf("%d",&v);
  printf("%d\n",sum - v);
}