43 lines
1.3 KiB
Python
43 lines
1.3 KiB
Python
# Copyright 2010-2017 Google
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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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"""Simple model with a reified constraint."""
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from __future__ import absolute_import
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from __future__ import division
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from __future__ import print_function
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from ortools.sat.python import cp_model
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def ReifiedSample():
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"""Showcase creating a reified constraint."""
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model = cp_model.CpModel()
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x = model.NewBoolVar('x')
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y = model.NewBoolVar('y')
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b = model.NewBoolVar('b')
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# First version using a half-reified bool and.
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model.AddBoolAnd([x, y.Not()]).OnlyEnforceIf(b)
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# Second version using implications.
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model.AddImplication(b, x)
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model.AddImplication(b, y.Not())
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# Third version using bool or.
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model.AddBoolOr([b.Not(), x])
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model.AddBoolOr([b.Not(), y.Not()])
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ReifiedSample()
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