algorithm.h

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/* xoreos - A reimplementation of BioWare's Aurora engine
 *
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 * xoreos is free software; you can redistribute it and/or
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/* Based on ScummVM (<http://scummvm.org>) code, which is released
 * under the terms of version 2 or later of the GNU General Public
 * License.
 *
 * The original copyright note in ScummVM reads as follows:
 *
 * ScummVM is the legal property of its developers, whose names
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 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
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#ifndef COMMON_ALGORITHM_H
#define COMMON_ALGORITHM_H

namespace Common {

template<class T>
T gcd(T a, T b) {
    // Note: We check for <= instead of < to avoid spurious compiler
    // warnings if T is an unsigned type, i.e. warnings like "comparison
    // of unsigned expression < 0 is always false".
    if (a <= 0)
        a = -a;
    if (b <= 0)
        b = -b;

    while (a > 0) {
        T tmp = a;
        a = b % a;
        b = tmp;
    }

    return b;
}

} // End of namespace Common

#endif