68 lines
2.2 KiB
Python
68 lines
2.2 KiB
Python
#!/usr/bin/env python3
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# Copyright 2010-2022 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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"""A simple knapsack problem."""
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# [START program]
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# [START import]
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from ortools.algorithms import pywrapknapsack_solver
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# [END import]
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def main():
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# Create the solver.
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# [START solver]
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solver = pywrapknapsack_solver.KnapsackSolver(
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pywrapknapsack_solver.KnapsackSolver.
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KNAPSACK_MULTIDIMENSION_BRANCH_AND_BOUND_SOLVER, 'KnapsackExample')
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# [END solver]
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# [START data]
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values = [
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360, 83, 59, 130, 431, 67, 230, 52, 93, 125, 670, 892, 600, 38, 48, 147,
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78, 256, 63, 17, 120, 164, 432, 35, 92, 110, 22, 42, 50, 323, 514, 28,
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87, 73, 78, 15, 26, 78, 210, 36, 85, 189, 274, 43, 33, 10, 19, 389, 276,
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312
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]
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weights = [[
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7, 0, 30, 22, 80, 94, 11, 81, 70, 64, 59, 18, 0, 36, 3, 8, 15, 42, 9, 0,
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42, 47, 52, 32, 26, 48, 55, 6, 29, 84, 2, 4, 18, 56, 7, 29, 93, 44, 71,
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3, 86, 66, 31, 65, 0, 79, 20, 65, 52, 13
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]]
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capacities = [850]
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# [END data]
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# [START solve]
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solver.Init(values, weights, capacities)
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computed_value = solver.Solve()
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# [END solve]
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# [START print_solution]
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packed_items = []
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packed_weights = []
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total_weight = 0
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print('Total value =', computed_value)
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for i in range(len(values)):
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if solver.BestSolutionContains(i):
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packed_items.append(i)
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packed_weights.append(weights[0][i])
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total_weight += weights[0][i]
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print('Total weight:', total_weight)
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print('Packed items:', packed_items)
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print('Packed_weights:', packed_weights)
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# [END print_solution]
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if __name__ == '__main__':
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main()
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# [END program]
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