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 code2{
  
      static final int M = 1000000007;
  
      // Fast input 
      static class Hrittik_FastReader{
          StringTokenizer st;
          BufferedReader br;
          public int n;
          public Hrittik_FastReader(){
              br=new BufferedReader(new InputStreamReader(System.in));
          }
          String next(){
              while(st==null || !st.hasMoreTokens()){
                  try {
                      st=new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
          String nextLine(){
              String str="";
              try {
                  str=br.readLine().trim();
              } catch (Exception e) {
                  e.printStackTrace();
              }
              return str;
          }
          double nextDouble(){
              return Double.parseDouble(next());
          }
          int nextInt(){
              return Integer.parseInt(next());
          }
          long nextLong(){
              return Long.parseLong(next());
          }
          
          
      }
      // Fast output
      static class Hrittik_FastWriter {
          private final BufferedWriter bw;
  
          public Hrittik_FastWriter() {
              this.bw = new BufferedWriter(new OutputStreamWriter(System.out));
          }
  
          public void println(Object object) throws IOException {
              print(object);
              bw.append("\n");
          }
  
          public void print(Object object) throws IOException {
              bw.append("" + object);
  
          }
  
          public void close() throws IOException {
              bw.close();
          }
      }
  
      /**
       * 
       * @param a
       * @param b
       * @return gcd of two numbers using recursion
       */
      private static int gcd(int a , int b){
          if(b == 0) return a;
          return gcd(b, a%b);
      }
  
  
      public static void main(String[] args) {
  
          try {
              Hrittik_FastReader Sc =new Hrittik_FastReader();
              Hrittik_FastWriter out = new Hrittik_FastWriter();
              int t = Sc.nextInt();
              while(t-- > 0){
                  // write your code here
                  int n = Sc.nextInt();
                  int a[] = new int[n];
                  for(int i = 0; i < n; i++){
                      a[i] = Sc.nextInt();
                  }
                  int ans = 1;
                  if(a[0] == 1){
                      ans++;
                  }
                  
                  for(int i = 1; i < n; i++){
                      if(a[i] == 0 && a[i - 1] == 0){
                          ans = -1;
                          break;
                      }
                      else if(a[i] == 1 && a[i - 1] == 1){
                          ans += 5;
                      }
                      else if(a[i] == 1 && a[i - 1] == 0){
                          ans += 1;
                      }
                  }
                  out.println(ans);
                 
  
                  
                  
                  
              }
              out.close();
          }
  
          catch (Exception e) {
              return;
          }
      }
  }
  
  