mirrors
/
OpenTTD
mirror of https://github.com/OpenTTD/OpenTTD.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

Remove: LeastCommonMultiple / GreatestCommonDivisor 

Use std::lcm / std::gcd instead.
This commit is contained in:
Rubidium 2024-01-20 15:59:53 +01:00 committed by rubidium42
parent 1403f24fa9
commit 4c51534b6a
3 changed files with 0 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
src/core/math_func.cpp
View File

@ -12,41 +12,6 @@
#include "../safeguards.h"
/**
* Compute least common multiple (lcm) of arguments \a a and \a b, the smallest
* integer value that is a multiple of both \a a and \a b.
* @param a First number.
* @param b second number.
* @return Least common multiple of values \a a and \a b.
*
* @note This function only works for non-negative values of \a a and \a b.
*/
int LeastCommonMultiple(int a, int b)
{
if (a == 0 || b == 0) return 0; // By definition.
if (a == 1 || a == b) return b;
if (b == 1) return a;
return a * b / GreatestCommonDivisor(a, b);
}
/**
* Compute greatest common divisor (gcd) of \a a and \a b.
* @param a First number.
* @param b second number.
* @return Greatest common divisor of \a a and \a b.
*/
int GreatestCommonDivisor(int a, int b)
{
while (b != 0) {
int t = b;
b = a % b;
a = t;
}
return a;
}
/**
* Deterministic approximate division.
* Cancels out division errors stemming from the integer nature of the division over multiple runs.

2
src/core/math_func.hpp
View File

@ -309,8 +309,6 @@ inline uint ToPercent16(uint i)
return i * 101 >> 16;
}
int LeastCommonMultiple(int a, int b);
int GreatestCommonDivisor(int a, int b);
int DivideApprox(int a, int b);
/**

35
src/tests/math_func.cpp
View File

@ -13,41 +13,6 @@
#include "../core/math_func.hpp"
TEST_CASE("LeastCommonMultipleTest - Zero")
{
CHECK(0 == LeastCommonMultiple(0, 0));
CHECK(0 == LeastCommonMultiple(0, 600));
CHECK(0 == LeastCommonMultiple(600, 0));
}
TEST_CASE("LeastCommonMultipleTest - FindLCM")
{
CHECK(25 == LeastCommonMultiple(5, 25));
CHECK(25 == LeastCommonMultiple(25, 5));
CHECK(130 == LeastCommonMultiple(5, 26));
CHECK(130 == LeastCommonMultiple(26, 5));
}
TEST_CASE("GreatestCommonDivisorTest - Negative")
{
CHECK(4 == GreatestCommonDivisor(4, -52));
// CHECK(3 == GreatestCommonDivisor(-27, 6)); // error - returns -3
}
TEST_CASE("GreatestCommonDivisorTest - Zero")
{
CHECK(27 == GreatestCommonDivisor(0, 27));
CHECK(27 == GreatestCommonDivisor(27, 0));
}
TEST_CASE("GreatestCommonDivisorTest - FindGCD")
{
CHECK(5 == GreatestCommonDivisor(5, 25));
CHECK(5 == GreatestCommonDivisor(25, 5));
CHECK(1 == GreatestCommonDivisor(7, 27));
CHECK(1 == GreatestCommonDivisor(27, 7));
}
TEST_CASE("DivideApproxTest - Negative")
{
CHECK(-2 == DivideApprox(-5, 2));