comefrom: <doocs>1100.Find K-Length Substrings With No Repeated Characters_1.py
code: def numKLenSubstrNoRepeats( s: str, k: int) -> int:
      ans = j = 0
      mp = {}
      for i, c in enumerate(s):
          if c in mp:
              j = max(j, mp[c] + 1)
          mp[c] = i
          if i - j + 1 >= k:
              ans += 1
      return ans
masked: def sample_funcname ( var_0 : str , var_1 : int ) -> int :
      var_3 = var_2 = 0
      var_4 = { }
      for var_5 , var_6 in enumerate ( var_0 ) :
          if var_6 in var_4 :
              var_2 = max ( var_2 , var_4 [ var_6 ] + 1 )
          var_4 [ var_6 ] = var_5
          if var_5 - var_2 + 1 >= var_1 :
              var_3 += 1
      return var_3
  