description: Petya has got an interesting flower. Petya is a busy person, so he sometimes forgets to water it. You are given n days from Petya's live and you have to determine what happened with his flower in the end.
  
  The flower grows as follows: 
  
    * If the flower isn't watered for two days in a row, it dies. 
    * If the flower is watered in the i-th day, it grows by 1 centimeter. 
    * If the flower is watered in the i-th and in the (i-1)-th day (i > 1), then it grows by 5 centimeters instead of 1. 
    * If the flower is not watered in the i-th day, it does not grow. 
  
  
  
  At the beginning of the 1-st day the flower is 1 centimeter tall. What is its height after n days?
  
  Input
  
  Each test contains multiple test cases. The first line contains the number of test cases t (1 ≤ t ≤ 100). Description of the test cases follows.
  
  The first line of each test case contains the only integer n (1 ≤ n ≤ 100).
  
  The second line of each test case contains n integers a_1, a_2, ..., a_n (a_i = 0 or a_i = 1). If a_i = 1, the flower is watered in the i-th day, otherwise it is not watered.
  
  Output
  
  For each test case print a single integer k — the flower's height after n days, or -1, if the flower dies.
  
  Example
  
  Input
  
  
  4
  3
  1 0 1
  3
  0 1 1
  4
  1 0 0 1
  1
  0
  
  
  Output
  
  
  3
  7
  -1
  1
solution: #include <bits/stdc++.h>
  using namespace std;
  using ll = long long;
  using ld = long double;
  using vll = vector<long long>;
  ll gcd(ll a, ll b) {
    if (b == 0) return a;
    return gcd(b, a % b);
  }
  ll lcm(ll a, ll b) { return (a / gcd(a, b)) * b; }
  ll power(ll a, ll b) {
    ll ans = 1;
    while (b) {
      if (b % 2 == 1) {
        ans = (ans * a);
      }
      a = (a * a);
      b /= 2;
    }
    return ans;
  }
  ll solve(ll g) {
    ll n;
    cin >> n;
    vll v(n, 0);
    for (ll i = 0; i < n; i++) cin >> v[i];
    ll cnt0 = 1 - v[0], cnt1 = v[0];
    ll ans = 1 + v[0];
    for (ll i = 1; i < n; i++) {
      if (v[i] == 0) {
        cnt0++;
        cnt1 = 0;
        if (cnt0 > 1) {
          cout << -1 << '\n';
          return 0;
        }
      } else {
        cnt0 = 0;
        if (cnt1 >= 1) {
          ans += 5;
        } else {
          ans += 1;
        }
        cnt1++;
      }
    }
    cout << ans << '\n';
    return 0;
  }
  signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    ll x = 1;
    ll t;
    cin >> t;
    while (t--) {
      ll z = solve(x);
    }
  }
  