70 lines
2.0 KiB
C++
70 lines
2.0 KiB
C++
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// This may look like C code, but it is really -*- C++ -*-
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// ------------------------------------------------------------------
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// The Goldware Library
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// Copyright (C) 1990-1999 Odinn Sorensen
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// ------------------------------------------------------------------
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Library General Public
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// License as published by the Free Software Foundation; either
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// version 2 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Library General Public License for more details.
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//
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// You should have received a copy of the GNU Library General Public
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// License along with this program; if not, write to the Free
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// Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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// MA 02111-1307, USA
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// ------------------------------------------------------------------
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// $Id$
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// ------------------------------------------------------------------
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// Reverse Polish Notation expression evaluator class.
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// ------------------------------------------------------------------
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#include <geval.h>
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// ------------------------------------------------------------------
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gevalrpn::gevalrpn() {
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}
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// ------------------------------------------------------------------
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gevalrpn::~gevalrpn() {
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}
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// ------------------------------------------------------------------
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int gevalrpn::evaluate() {
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ops o;
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int x, y=0;
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while(ostk.size()) {
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o = pop_operator();
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switch(o) {
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case negation:
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case logic_not:
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x = pop_value();
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break;
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default:
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x = pop_value();
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y = pop_value();
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}
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push_value(evaluate_op(o, y, x));
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}
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return pop_value();
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}
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// ------------------------------------------------------------------
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