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#!/usr/bin/env python
###############################################################################
# Top contributors (to current version):
# Andres Noetzli, Aina Niemetz, Makai Mann
#
# 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
# through the Python API. This is a direct translation of sequences.cpp.
##
import cvc5
from cvc5 import Kind
if __name__ == "__main__":
tm = cvc5.TermManager()
slv = cvc5.Solver(tm)
# Set the logic
slv.setLogic("QF_SLIA")
# Produce models
slv.setOption("produce-models", "true")
# The option strings-exp is needed
slv.setOption("strings-exp", "true")
# Set output language to SMTLIB2
slv.setOption("output-language", "smt2")
# Sequence sort
int_seq = tm.mkSequenceSort(tm.getIntegerSort())
# Sequence variables
x = tm.mkConst(int_seq, "x")
y = tm.mkConst(int_seq, "y")
# Empty sequence
empty = tm.mkEmptySequence(tm.getIntegerSort())
# Sequence concatenation: x.y.empty
concat = tm.mkTerm(Kind.SEQ_CONCAT, x, y, empty)
# Sequence length: |x.y.empty|
concat_len = tm.mkTerm(Kind.SEQ_LENGTH, concat)
# |x.y.empty| > 1
formula1 = tm.mkTerm(Kind.GT, concat_len, tm.mkInteger(1))
# Sequence unit: seq(1)
unit = tm.mkTerm(Kind.SEQ_UNIT, tm.mkInteger(1))
# x = seq(1)
formula2 = tm.mkTerm(Kind.EQUAL, x, unit)
# Make a query
q = tm.mkTerm(Kind.AND, formula1, formula2)
# Check satisfiability
result = slv.checkSatAssuming(q)
print("cvc5 reports:", q, "is", result)
if result:
print("x = {}".format(slv.getValue(x)))
print("y = {}".format(slv.getValue(y)))
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