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#!/usr/bin/env python
###############################################################################
# Top contributors (to current version):
# Yoni Zohar
#
# 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 the solving capabilities of the cvc5 strings
# solver. A simple translation of the base python API.
# example.
##
from cvc5.pythonic import *
if __name__ == "__main__":
str_ab = "ab"
# String constants
ab = StringVal(str_ab)
abc = StringVal("abc")
# String variables
x = String("x")
y = String("y")
z = String("z")
# String concatenation: x.ab.y
lhs = Concat(x, ab, y)
# String concatenation: abc.z
rhs = Concat(abc, z)
# x.ab.y = abc.z
formula1 = (lhs == rhs)
# Length of y: |y|
leny = Length(y)
# |y| >= 0
formula2 = leny >= 0
# Regular expression: (ab[c-e]*f)|g|h
r = Union(Concat(Re("ab"), Star(Range("c", "e")), Re("f")), Re("g"), Re("h"))
# String variables
s1 = String("s1")
s2 = String("s2")
# String concatenation: s1.s2
s = Concat(s1, s2)
# s1.s2 in (ab[c-e]*f)|g|h
formula3 = InRe(s,r)
# Make a query
q = And(formula1, formula2, formula3)
# check sat
s = Solver()
s.add(q)
assert sat == s.check()
m = s.model()
print("x = ", m[x])
print(" s1.s2 =", m[Concat(s1, s2)])
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