comefrom: <doocs>0852.Peak Index in a Mountain Array_1.py
code: def peakIndexInMountainArray( arr: List[int]) -> int:
      left, right = 1, len(arr) - 2
      while left < right:
          mid = (left + right) >> 1
          if arr[mid] > arr[mid + 1]:
              right = mid
          else:
              left = mid + 1
      return left
masked: def sample_funcname ( var_0 : List [ int ] ) -> int :
      var_1 , var_2 = 1 , len ( var_0 ) - 2
      while var_1 < var_2 :
          var_3 = ( var_1 + var_2 ) >> 1
          if var_0 [ var_3 ] > var_0 [ var_3 + 1 ] :
              var_2 = var_3
          else :
              var_1 = var_3 + 1
      return var_1
  