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#!/usr/bin/env python
###############################################################################
# Top contributors (to current version):
# Aina Niemetz, Mudathir Mohamed
#
# This file is part of the cvc5 project.
#
# Copyright (c) 2009-2025 by the authors listed in the file AUTHORS
# in the top-level source directory and their institutional affiliations.
# All rights reserved. See the file COPYING in the top-level source
# directory for licensing information.
# #############################################################################
#
# A simple demonstration of reasoning about bags.
##
import cvc5
from cvc5 import Kind
if __name__ == "__main__":
tm = cvc5.TermManager()
slv = cvc5.Solver(tm)
slv.setLogic("ALL")
# Produce models
slv.setOption("produce-models", "true")
slv.setOption("incremental", "true")
bag = tm.mkBagSort(tm.getStringSort())
A = tm.mkConst(bag, "A")
B = tm.mkConst(bag, "B")
C = tm.mkConst(bag, "C")
x = tm.mkConst(tm.getStringSort(), "x")
intersectionAC = tm.mkTerm(Kind.BAG_INTER_MIN, A, C)
intersectionBC = tm.mkTerm(Kind.BAG_INTER_MIN, B, C)
# union disjoint does not distribute over intersection
unionDisjointAB = tm.mkTerm(Kind.BAG_UNION_DISJOINT, A, B)
lhs = tm.mkTerm(Kind.BAG_INTER_MIN, unionDisjointAB, C)
rhs = tm.mkTerm(Kind.BAG_UNION_DISJOINT, intersectionAC, intersectionBC)
guess = tm.mkTerm(Kind.EQUAL, lhs, rhs)
print("cvc5 reports: {} is {}".format(
guess.notTerm(), slv.checkSatAssuming(guess.notTerm())))
print("{}: {}".format(A, slv.getValue(A)))
print("{}: {}".format(B, slv.getValue(B)))
print("{}: {}".format(C, slv.getValue(C)))
print("{}: {}".format(lhs, slv.getValue(lhs)))
print("{}: {}".format(rhs, slv.getValue(rhs)))
# union max distributes over intersection
unionMaxAB = tm.mkTerm(Kind.BAG_UNION_MAX, A, B)
lhs = tm.mkTerm(Kind.BAG_INTER_MIN, unionMaxAB, C)
rhs = tm.mkTerm(Kind.BAG_UNION_MAX, intersectionAC, intersectionBC)
theorem = tm.mkTerm(Kind.EQUAL, lhs, rhs)
print("cvc5 reports: {} is {}.".format(
theorem.notTerm(), slv.checkSatAssuming(theorem.notTerm())))
# Verify emptbag is a subbag of any bag
emptybag = tm.mkEmptyBag(bag)
theorem = tm.mkTerm(Kind.BAG_SUBBAG, emptybag, A)
print("cvc5 reports: {} is {}.".format(
theorem.notTerm(), slv.checkSatAssuming(theorem.notTerm())))
# find an element with multiplicity 4 in the disjoint union of
# {|"a", "a", "b", "b", "b"|} and {|"b", "c", "c"|}
one = tm.mkInteger(1)
two = tm.mkInteger(2)
three = tm.mkInteger(3)
four = tm.mkInteger(4)
a = tm.mkString("a")
b = tm.mkString("b")
c = tm.mkString("c")
bag_a_2 = tm.mkTerm(Kind.BAG_MAKE, a, two)
bag_b_3 = tm.mkTerm(Kind.BAG_MAKE, b, three)
bag_b_1 = tm.mkTerm(Kind.BAG_MAKE, b, one)
bag_c_2 = tm.mkTerm(Kind.BAG_MAKE, c, two)
bag_a_2_b_3 = tm.mkTerm(Kind.BAG_UNION_DISJOINT, bag_a_2, bag_b_3)
bag_b_1_c_2 = tm.mkTerm(Kind.BAG_UNION_DISJOINT, bag_b_1, bag_c_2)
UnionDisjoint = tm.mkTerm(
Kind.BAG_UNION_DISJOINT, bag_a_2_b_3, bag_b_1_c_2)
count_x = tm.mkTerm(Kind.BAG_COUNT, x, UnionDisjoint)
e = tm.mkTerm(Kind.EQUAL, four, count_x)
result = slv.checkSatAssuming(e)
print("cvc5 reports: {} is {}.".format(e, result))
if result.isSat():
print("{}: {} ".format(x, slv.getValue(x)))
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