source_code: import java.util.*;
  import java.io.*;
  
  public class _1523_C {
      public static void main(String[] args) throws IOException {
          BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
          PrintWriter out = new PrintWriter(System.out);
          int t = Integer.parseInt(in.readLine());
          while(t-- > 0) {
              int n = Integer.parseInt(in.readLine());
              int[] a = new int[n];
              for(int i = 0; i < n; i++) {
                  a[i] = Integer.parseInt(in.readLine());
              }
              boolean[][] used = new boolean[n][n + 1];
              boolean[] used2 = new boolean[n];
              String[][] res = new String[n][2];
              res[0][0] = "1";
              res[0][1] = "";
              for(int i = 1; i < n; i++) {
                  if(a[i] == 1) {
                      for(int j = i - 1; j >= 0; j--) {
                          if(!used[j][a[i]] && !used2[j]) {
                              res[i][0] = res[j][0] + ".1";
                              res[i][1] = res[j][0];
                              used[j][a[i]] = true;
                              break;
                          }
                      }
                  }else {
                      for(int j = i - 1; j >= 0; j--) {
                          if(!used[j][a[i]] && !used2[j] && a[j] == a[i] - 1) {
                              if(res[j][1].equals("")) {
                                  res[i][0] = "" + a[i];
                              }else {
                                  res[i][0] = res[j][1] + "." + a[i];
                              }
                              res[i][1] = res[j][1];
                              used[j][a[i]] = true;
                              break;
                          }
                          used2[j] = true;
                      }
                  }
              }
              for(int i = 0; i < n; i++) {
                  out.println(res[i][0]);
              }
          }
          in.close();
          out.close();
      }
  }
  