description: It is a simplified version of problem F2. The difference between them is the constraints (F1: k ≤ 2, F2: k ≤ 10).
  
  You are given an integer n. Find the minimum integer x such that x ≥ n and the number x is k-beautiful.
  
  A number is called k-beautiful if its decimal representation having no leading zeroes contains no more than k different digits. E.g. if k = 2, the numbers 3434443, 55550, 777 and 21 are k-beautiful whereas the numbers 120, 445435 and 998244353 are not.
  
  Input
  
  The first line contains one integer t (1 ≤ t ≤ 10^4) — the number of test cases. Then t test cases follow.
  
  Each test case consists of one line containing two integers n and k (1 ≤ n ≤ 10^9, 1 ≤ k ≤ 2).
  
  Output
  
  For each test case output on a separate line x — the minimum k-beautiful integer such that x ≥ n.
  
  Example
  
  Input
  
  
  4
  1 1
  221 2
  177890 2
  998244353 1
  
  
  Output
  
  
  1
  221
  181111
  999999999
solution: def solve(num, k):
      count = 0
      tab = [-1 for _ in range(int(k))]
      idx = 0
      rem = -1
      rem_idx = -1
      for x in num:
          if int(x) not in tab:
              if count < int(k):
                  tab[count] = int(x)
                  count += 1
              else:
                  rem = int(x)
                  rem_idx = idx
                  break
          idx += 1
  
      if rem == -1:
          print(num)
          return
  
      idx_1 = 0
      # idx_2 = 0
      # sec_tab = []
      # for x in range(rem_idx, -1, -1):
      #     if int(num[x]) < max(tab):
      #         idx_1 = x
      #         break
      # for x in range(rem_idx+1):
  
      check = False
      counter = 0
      sec_tab = []
      new = min(tab)
      if max(rem, max(tab)) == rem:
          for x in range(rem_idx, -1, -1):
              if int(num[x]) < max(tab):
                  idx_1 = x
                  break
  
          for x in range(rem_idx + 1):
              if int(num[x]) not in sec_tab:
                  if counter == count-1:
                      idx_2 = x
                      break
                  else:
                      counter += 1
                      sec_tab.append(int(num[x]))
  
          if idx_2 >= idx_1:
              counter = 0
              for x in num:
                  if int(x) not in sec_tab and not check:
                      print(int(x)+1, end = "")
                      check = True
                      if int(x)+1 not in sec_tab:
                          sec_tab.append(int(x)+1)
  
                      if len(sec_tab) == count:
                          new = min(sec_tab)
                      else:
                          new = 0
  
                          # if int(x) == min(tab):
                          # if int(x) == min(tab) and int(x)+1 in tab:
                          #     new = 0
                          # elif int(x)+1 not in tab:
                          #     if int(x) == min(tab):
                          #         new = int(x)+1
                          #         # for i in range(len(tab)):
                          #         #     if tab[i] == int(x):
                          #         #         tab[i] += 1
                          #         #         break
                          #     else:
                          #         new = min([i for i in range(10) if i not in tab or i == int(x)])
  
                  # elif int(x) in sec_tab:
                  #     print(int(x), end = "")
  
                  elif not check:
                      print(int(x), end="")
  
                  else:
                      print(new, end="")
  
              print()
  
          else:
              temp = min([i for i in tab if i > int(num[idx_1])])
              for j in range(len(num)):
                  if j < idx_1:
                      print(num[j], end = "")
                  elif j == idx_1:
                      print(temp, end = "")
                  else:
                      print(min(tab), end = "")
              print()
  
  
      else:
          temp = min([i for i in tab if i > rem])
          for x in num:
              if int(x) not in sec_tab and not check:
                  if counter == count:
                      print(temp, end="")
                      check = True
                  else:
                      sec_tab.append(int(x))
                      counter += 1
                      print(int(x), end="")
  
              elif not check:
                  print(int(x), end="")
  
              else:
                  print(min(tab), end="")
  
          print()
  
  
  for i in range(int(input())):
      num, k = map(str, input().split())
      solve(num, k)