80 lines
2.6 KiB
C++
80 lines
2.6 KiB
C++
/*
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This file is part of Warzone 2100.
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Copyright (C) 1999-2004 Eidos Interactive
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Copyright (C) 2005-2013 Warzone 2100 Project
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Warzone 2100 is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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Warzone 2100 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
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Warzone 2100; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/*!
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* \file
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* \brief Rational number classes.
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*/
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#ifndef RATIONAL_H
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#define RATIONAL_H
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#include <algorithm>
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static inline int gcd(int a, int b)
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{
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while (b != 0)
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{
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a %= b;
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std::swap(a, b);
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}
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return abs(a);
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}
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/// Simple rational numbers, not bignum.
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struct Rational
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{
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Rational() {}
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Rational(int numerator, int denominator = 1)
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{
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int g = gcd(numerator, denominator);
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g *= denominator > 0? 1 : -1;
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n = numerator/g;
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d = denominator/g;
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}
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bool operator ==(Rational const &b) const { return n*b.d == b.n*d; }
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bool operator !=(Rational const &b) const { return n*b.d != b.n*d; }
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bool operator < (Rational const &b) const { return n*b.d < b.n*d; }
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bool operator <=(Rational const &b) const { return n*b.d <= b.n*d; }
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bool operator > (Rational const &b) const { return n*b.d > b.n*d; }
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bool operator >=(Rational const &b) const { return n*b.d >= b.n*d; }
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Rational operator +(Rational const &b) const { return Rational(n*b.d + b.n*d, d*b.d); }
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Rational operator -(Rational const &b) const { return Rational(n*b.d - b.n*d, d*b.d); }
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Rational operator *(Rational const &b) const { return Rational(n*b.n, d*b.d); }
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Rational operator /(Rational const &b) const { return Rational(n*b.d, d*b.n); }
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Rational operator -() const { return Rational(-n, d); }
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Rational &operator +=(Rational const &b) { return *this = *this + b; }
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Rational &operator -=(Rational const &b) { return *this = *this - b; }
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Rational &operator *=(Rational const &b) { return *this = *this * b; }
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Rational &operator /=(Rational const &b) { return *this = *this / b; }
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int floor() const { return n >= 0? n/d : (n - (d - 1))/d; }
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int ceil() const { return n >= 0? (n + (d - 1))/d : n/d; }
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// If int16_t isn't big enough, the comparison operations might overflow.
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int16_t n;
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int16_t d;
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private:
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Rational(float); // Disable.
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Rational(double); // Disable.
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};
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#endif //RATIONAL_H
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