c34026b101
note: done using ```sh git grep -l "2010-2024 Google" | xargs sed -i 's/2010-2024 Google/2010-2025 Google/' ```
80 lines
2.3 KiB
Python
Executable File
80 lines
2.3 KiB
Python
Executable File
#!/usr/bin/env python3
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# Copyright 2010-2025 Google LLC
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""This model implements a sudoku solver."""
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from ortools.sat.python import cp_model
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def solve_sudoku() -> None:
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"""Solves the sudoku problem with the CP-SAT solver."""
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# Create the model.
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model = cp_model.CpModel()
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cell_size = 3
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line_size = cell_size**2
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line = list(range(0, line_size))
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cell = list(range(0, cell_size))
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initial_grid = [
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[0, 6, 0, 0, 5, 0, 0, 2, 0],
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[0, 0, 0, 3, 0, 0, 0, 9, 0],
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[7, 0, 0, 6, 0, 0, 0, 1, 0],
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[0, 0, 6, 0, 3, 0, 4, 0, 0],
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[0, 0, 4, 0, 7, 0, 1, 0, 0],
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[0, 0, 5, 0, 9, 0, 8, 0, 0],
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[0, 4, 0, 0, 0, 1, 0, 0, 6],
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[0, 3, 0, 0, 0, 8, 0, 0, 0],
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[0, 2, 0, 0, 4, 0, 0, 5, 0],
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]
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grid = {}
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for i in line:
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for j in line:
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grid[(i, j)] = model.new_int_var(1, line_size, "grid %i %i" % (i, j))
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# AllDifferent on rows.
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for i in line:
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model.add_all_different(grid[(i, j)] for j in line)
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# AllDifferent on columns.
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for j in line:
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model.add_all_different(grid[(i, j)] for i in line)
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# AllDifferent on cells.
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for i in cell:
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for j in cell:
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one_cell = []
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for di in cell:
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for dj in cell:
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one_cell.append(grid[(i * cell_size + di, j * cell_size + dj)])
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model.add_all_different(one_cell)
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# Initial values.
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for i in line:
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for j in line:
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if initial_grid[i][j]:
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model.add(grid[(i, j)] == initial_grid[i][j])
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# Solves and prints out the solution.
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solver = cp_model.CpSolver()
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status = solver.solve(model)
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if status == cp_model.OPTIMAL:
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for i in line:
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print([int(solver.value(grid[(i, j)])) for j in line])
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solve_sudoku()
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