output_description: Print the number of ways she can travel to the bottom-right cell, modulo
  10^9+7.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      H W A B
attempt: n, k = map(int, input().rstrip().split())
  dislikes = list(map(int, input().rstrip().split()))
  n = str(n)
  len_n = len(n)
  separate_n = [int(s) for s in n]
  
  pay = separate_n.copy()
  up_nextlevel = False
  for i in range(len(separate_n) - 1, -1, -1):
      up_nextlevel = False
      if separate_n[i] in dislikes:
          for j in range(10):
              num = separate_n[i] + j
              if num > 9:
                  num -= 10
                  up_nextlevel = True
              if not (num in dislikes):
                  pay[i] = num
                  break
      else:
          continue
  if up_nextlevel:
      for i in range(1, 10):
          if not (i in dislikes):
              print(i, end="")
              break
  for p in pay:
      print(p, end="")
  
problem_description: Statement
  
  We have a large square grid with H rows and W columns. Iroha is now standing
  in the top-left cell. She will repeat going right or down to the adjacent
  cell, until she reaches the bottom-right cell.
  
  However, she cannot enter the cells in the intersection of the bottom A rows
  and the leftmost B columns. (That is, there are A×B forbidden cells.) There is
  no restriction on entering the other cells.
  
  Find the number of ways she can travel to the bottom-right cell.
  
  Since this number can be extremely large, print the number modulo 10^9+7.
samples: [{"input": "2 3 1 1", "output": "2\n    \n\nWe have a 2\u00d73 grid, but entering the bottom-left cell is forbidden. The number\nof ways to travel is two: \"Right, Right, Down\" and \"Right, Down, Right\".\n\n* * *"}, {"input": "10 7 3 4", "output": "3570\n    \n\nThere are 12 forbidden cells.\n\n* * *"}, {"input": "100000 100000 99999 99999", "output": "1\n    \n\n* * *"}, {"input": "100000 100000 44444 55555", "output": "738162020"}]