Constraint solving using backtracking

sum-problem.py

#!/usr/bin/env python

import libConstraint as LC



solution = LC.Solution()


@solution.must_satisfy
def sum_constraint( params, candidate ):
    S = sum( candidate )
        if S > 10:
            return False
    return True

@solution.must_satisfy
def begin_constraint( params, candidate ):
    if len( candidate ) > 2:
        if candidate[:2] != [1,2]:
            return False
    return True


@solution.is_valid
def valid_solution( params, candidate ):
    S = sum( candidate )
    return S == 10


import pprint


pprint.pprint( solution.get( domain = [1,2,3,4,5,10,11] ) )