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.util.*;
  import java.io.*;
  public class S{
      public static void main (String [] args)throws IOException{
          BufferedReader br = new BufferedReader (new InputStreamReader (System.in));
          int t = Integer.parseInt(br.readLine());
          while (t-->0){
              int n =Integer.parseInt(br.readLine());
              int ar[]= new int[n];
              StringTokenizer st = new StringTokenizer (br.readLine());
              for (int i =0;i<n;i++){
                  ar[i]= Integer.parseInt(st.nextToken());
              }
              int k =1;
              if (ar[0]==1) k++;
              for (int i =1;i<n;i++){
                  if (ar[i]==0){
                      if (ar[i-1]==0){
                          k=-1;
                          break;
                      }
                  }
                  else{
                      if (ar[i-1]==1){
                          k+=5;
                      }
                      else k++;
                  }
              }
              System.out.println (k);
          }
      }
  }