#include <bits/stdc++.h>
using namespace std;
#include <math.h>
#include <iomanip>
#include <cstdint>
#include <string>
#include <sstream>

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
#define rep(i,n) for (int i = 0; i < (n); ++i)
typedef long long ll;
using P = pair<int,int>;

const int INF=1001001001;
const int mod =1e9+7;

int main() {
  int t;
  cin>>t;
  rep(z,t){
    int n;
    cin>>n;
    double sum=1;
    rep(i,n){
      double a;
      cin>>a;
      sum*=a+1;
    }
    cout<<sum-1<<endl;
  }
  return 0;
}