# Copyright 2010 Hakan Kjellerstrand hakank@bonetmail.com
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
toNum in Google CP Solver.
Convert a number <-> array of int in a specific base.
This model was created by Hakan Kjellerstrand (hakank@bonetmail.com)
Also see my other Google CP Solver models:
http://www.hakank.org/google_or_tools/
"""
from ortools.constraint_solver import pywrapcp
#
# converts a number (s) <-> an array of integers (t) in the specific base.
#
def toNum(solver, t, s, base):
tlen = len(t)
solver.Add(
s == solver.Sum([(base ** (tlen - i - 1)) * t[i] for i in range(tlen)]))
def main(unused_argv):
# Create the solver.
solver = pywrapcp.Solver("toNum test")
# data
n = 4
base = 10
# declare variables
x = [solver.IntVar(0, n - 1, "x%i" % i) for i in range(n)]
y = solver.IntVar(0, 10 ** n - 1, "y")
#
# constraints
#
# solver.Add(solver.AllDifferent([x[i] for i in range(n)]))
solver.Add(solver.AllDifferent(x))
# solver.Add(x[0] > 0) # just for fun
toNum(solver, x, y, base)
#
# solution and search
#
solution = solver.Assignment()
solution.Add([x[i] for i in range(n)])
solution.Add(y)
collector = solver.AllSolutionCollector(solution)
solver.Solve(solver.Phase([x[i] for i in range(n)],
solver.CHOOSE_FIRST_UNBOUND,
solver.ASSIGN_MIN_VALUE),
[collector])
num_solutions = collector.SolutionCount()
for s in range(num_solutions):
print "x:", [collector.Value(s, x[i]) for i in range(n)]
print "y:", collector.Value(s, y)
print
print "failures:", solver.Failures()
print "branches:", solver.Branches()
print "WallTime:", solver.WallTime()
if __name__ == "__main__":
main("cp sample")