# 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.

"""

  SEND+MOST=MONEY in Google CP Solver.


  Alphametic problem were we maximize MONEY.

  Problem from the lecture notes:
  http://www.ict.kth.se/courses/ID2204/notes/L01.pdf

  Compare with the following models:
  * Comet   : http://www.hakank.org/comet/send_most_money.co
  * Comet   : http://www.hakank.org/comet/send_most_money2.co
  * ECLiPSE : http://www.hakank.org/eclipse/send_most_money.ecl
  * SICStus: http://hakank.org/sicstus/send_most_money.pl
  * MiniZinc: http://www.hakank.org/minizinc/send_most_money.mzn
  * Gecode/R: http://www.hakank.org/gecode_r/send_most_money2.rb
  * Tailor/Essence': http://www.hakank.org/tailor/send_most_money.eprime
  * Zinc: http://www.hakank.org/minizinc/send_most_money.zinc


  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 constraint_solver import pywrapcp

def main(MONEY=0):

    # Create the solver.
    solver = pywrapcp.Solver('Send most money')

    # data


    # declare variables
    s = solver.IntVar(0,9,'s')
    e = solver.IntVar(0,9,'e')
    n = solver.IntVar(0,9,'n')
    d = solver.IntVar(0,9,'d')
    m = solver.IntVar(0,9,'m')
    o = solver.IntVar(0,9,'o')
    t = solver.IntVar(0,9,'t')
    y = solver.IntVar(0,9,'y')
    money = solver.IntVar(0,100000,'money')

    x = [s,e,n,d,m,o,t,y]



    #
    # constraints
    #
    if MONEY > 0:
        solver.Add(money == MONEY)

    solver.Add(solver.AllDifferent(x))
    solver.Add(money == m*10000 + o*1000 + n*100 + e*10 + y)
    solver.Add(money > 0)
    solver.Add(1000*s + 100*e + 10*n + d +
               1000*m + 100*o + 10*s + t ==
               money)
    solver.Add(s > 0)
    solver.Add(m > 0)


    #
    # solution and search
    #
    solution = solver.Assignment()
    solution.Add(x)
    solution.Add(money)

    collector = solver.AllSolutionCollector(solution)
    objective = solver.Maximize(money, 100)
    cargs = [collector]
    if MONEY == 0:
        objective = solver.Maximize(money, 1)
        cargs.extend([objective])

    solver.Solve(solver.Phase(x,
                              solver.CHOOSE_FIRST_UNBOUND,
                              solver.ASSIGN_MAX_VALUE),
                              cargs)

    num_solutions = collector.SolutionCount()
    money_val = 0
    for s in range(num_solutions):
        print "x:", [collector.Value(s, x[i]) for i in range(len(x))]
        money_val = collector.Value(s, money)
        print "money:", money_val
        print

    print "num_solutions:", num_solutions
    print "failures:", solver.Failures()
    print "branches:", solver.Branches()
    print "WallTime:", solver.WallTime()

    if MONEY == 0:
        return money_val



if __name__ == '__main__':
    # First get the maximised MONEY, and then show all solutions for
    # this value
    print "Minimize money..."
    money = main(0)
    print "\nCheck all solutions for money=%i" % money
    main(money)