mirror of https://github.com/OpenTTD/OpenTTD.git
42 lines
923 B
C++
42 lines
923 B
C++
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/* $Id$ */
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/** @file math_func.cpp Math functions. */
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#include "../stdafx.h"
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#include "math_func.hpp"
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/**
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* Compute least common multiple (lcm) of arguments \a a and \a b, the smallest
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* integer value that is a multiple of both \a a and \a b.
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* @param a First number.
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* @param b second number.
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* @return Least common multiple of values \a a and \a b.
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*
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* @note This function only works for non-negative values of \a a and \a b.
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*/
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int LeastCommonMultiple(int a, int b)
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{
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if (a == 0 || b == 0) return 0; // By definition.
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if (a == 1 || a == b) return b;
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if (b == 1) return a;
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return a * b / GreatestCommonDivisor(a, b);
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}
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/**
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* Compute greatest common divisor (gcd) of \a a and \a b.
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* @param a First number.
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* @param b second number.
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* @return Greatest common divisor of \a a and \a b.
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*/
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int GreatestCommonDivisor(int a, int b)
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{
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while (b != 0) {
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int t = b;
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b = a % b;
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a = t;
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}
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return a;
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}
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