75. class Coord: One location in the
grid
Each instance of this class represents the intersection of
a row and column, where a cell may occur (or not, if that
location is blank in the framework).
kkck
# - - - - - c l a s s C o o r d
class Coord(object):
'''Represents one location in the puzzle grid.
Exports:
Coord ( row, column ):
[ (row is a nonnegative row number) and
(column is a nonnegative column number) ->
return a new Coord representing the intersection of
row (row) and column (column) ]
.rc:
[ a two-tuple (self[0], self[1]); read-only ]
.__cmp__(self, other):
[ define an ordering with row number as the primary key
and column number as the secondary key ]
.__getitem__(self, isCol):
[ isCol is 0 ->
return self's row
isCol is 1 ->
return self's column ]
.__setitem__(self, isCol, value):
[ isCol is 0 ->
self[0] := value
isCol is 1 ->
self[1] := value ]
.__add__(self, other):
[ return a new Coord with row (self[0]+other[0]) and
column (self[1]+other[1]) ]
.__sub__(self, other):
[ return a new Coord with row (self[0]-other[0]) and
column (self[1]-other[1]) ]
.__str__(self): [ return a textual representation of self ]
'''
def __init__ ( self, row, col ):
self.rc = [row, col]
def __cmp__ ( self, other ):
return cmp ( self.rc, other.rc )
def __getitem__(self, isCol):
return self.rc[isCol]
def __setitem__(self, isCol, value):
self.rc[isCol] = value
def __add__ ( self, other ):
return Coord ( self[0]+other[0], self[1]+other[1] )
def __sub__ ( self, other ):
return Coord ( self[0]-other[0], self[1]-other[1] )
def __str__ ( self ):
return "(%d,%d)" % (self[0], self[1])
