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: 
  import java.beans.IntrospectionException;
  import java.util.*;
  import java.io.*;
  
  public class A {
      static int mod = (int) 1e9 + 7;
  
      public static void main(String[] args) throws IOException {
          BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
          StringBuilder stringBuilder = new StringBuilder();
          PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
  
          int T = Integer.parseInt(bufferedReader.readLine());
  
          while (T-- > 0) {
              int n=Integer.parseInt(bufferedReader.readLine());
              int arr[]=new int[n];
              StringTokenizer stringTokenizer=new StringTokenizer(bufferedReader.readLine());
              for (int i = 0; i < n; i++) {
                  arr[i]=Integer.parseInt(stringTokenizer.nextToken());
              }
              int count=1;
              boolean flag=true;
              for (int i = 0; i < n; i++) {
                  if (arr[i]==1){
                      count++;
                  }
                  if (i > 0 && arr[i-1]==1 && arr[i]==1){
                      count+=4;
                  }
  
                  if (i > 0 && arr[i-1]==0 && arr[i]==0)
                      flag=false;
              }
              if (flag==false)
                  out.println(-1);
              else out.println(count);
          }
          out.close();
      }
  
      public static long power(long a, int p) {
          long res = 1;
          while (p > 0) {
              if ((p & 1) == 1) res = (res * a) % mod;
              a = (a * a) % mod;
              p >>= 1;
          }
          return res;
      }
  
      static int gcd(int a, int b) {
          if (a == 0)
              return b;
          return gcd(b % a, a);
      }
  
      static int lcm(int a, int b) {
          return (a / gcd(a, b)) * b;
      }
  
  }