85 lines
2.5 KiB
Python
85 lines
2.5 KiB
Python
#!env python3
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# Eryn Wells <eryn@erynwells.me>
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'''
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A Sudoku puzzle solver.
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'''
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import itertools
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import math
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class Sudoku:
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def __init__(self, size=9):
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dim = math.sqrt(size)
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if dim != int(dim):
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raise ValueError('Board size must have an integral square root.')
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self._dimension = int(dim)
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self.size = size
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self.board = bytearray(b'\x00' * (size * size))
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@property
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def dimension(self):
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return self._dimension
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@property
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def rows(self):
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sz = self.size
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return [range(i * sz, i * sz + sz) for i in range(sz)]
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@property
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def columns(self):
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sz = self.size
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sz2 = sz ** 2
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return [range(i, sz2, sz) for i in range(sz)]
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@property
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def squares(self):
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dim = self.dimension
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return [self.square(x, y) for y in range(dim) for x in range(dim)]
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@property
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def solved(self):
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def _check_group(group):
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values = sorted([self.board[i] for i in group])
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is_complete = values == list(range(1, self.size+1))
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return is_complete
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sz = self.size
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sz2 = sz ** 2
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dim = int(math.sqrt(self.size))
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# TODO: WIP
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def square(self, x, y):
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dim = self.dimension
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if (x < 0 or x >= dim) or (y < 0 or y >= dim):
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raise IndexError('Invalid coordinates for square: ({}, {})'.format(x, y))
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offset = (x * dim, y * dim * self.size)
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def _range(i):
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start = (offset[1] + i * self.size) + offset[0]
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return range(start, start + dim)
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ranges = itertools.chain(*[_range(i) for i in range(dim)])
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return ranges
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def __str__(self):
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field_width = len(str(self.size))
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dim = int(math.sqrt(self.size))
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lines = []
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spacer = '+' + '+'.join(['-' * (field_width * dim) for _ in range(dim)]) + '+'
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for line in range(self.size):
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chunks = []
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for i in range(dim):
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fields = []
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for j in range(dim):
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idx = line * self.size + i * dim + j
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fields.append('{{board[{i}]:^{width}}}'.format(i=idx, width=field_width))
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chunks.append(''.join(fields))
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if (line % dim) == 0:
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lines.append(spacer)
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lines.append('|' + '|'.join(chunks) + '|')
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lines.append(spacer)
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fmt = '\n'.join(lines)
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str_board = [str(n) if n != 0 else ' ' for n in self.board]
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out = fmt.format(board=str_board)
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return out
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