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 check(s, k, t, n):
      # Check if the number s, but with last digit t, is k-beautiful.
      z = set()
      for i in range(len(s)):
          if(i == len(s)-1):
              z.add(t)
          else:
              z.add(int(s[i]))
      if(len(z)<=k):
          # Print the number
          needed = len(str(n)) - len(s)
          arr = []
          min_val = 9
          for i in range(len(s)):
              if(i == len(s)-1):
                  arr.append(t)
                  if(t < min_val):
                      min_val = t
              else:
                  arr.append(int(s[i]))
                  if(int(s[i])<min_val):
                      min_val = int(s[i])
          if(len(z)==k):
              for i in range(needed):
                  arr.append(min_val)
          else:
              for i in range(needed):
                  arr.append(0)
          for i in range(len(arr)):
              print(arr[i], end='')
          print()
          return True
      return False
  
  
  def func(n, i, k):
      # Check for the number from 0 to i.
      s = str(n)[0:i+1]
      t = int(s[-1]) + 1
      # Check k-beauty of s for [t ---> 9]
      while(t < 10):
          if(check(s, k, t, n)):
              # print(s, k, t)
  
              return 0
          else:
              t += 1
      func(n, i-1, k)
  
  for _ in range(int(input())):
      n, k = map(int, input().split())
      l = len(str(n))
      if(check(str(n), k, int(str(n)[-1]), n)):
          continue
      func(n, l-1, k)