Abstracted BaseX_2_10 to work with arbitrary containers and digit-types

This commit is contained in:
Leonetienne 2022-02-27 17:52:14 +01:00
parent e1cf366e25
commit 1903f19b96
3 changed files with 54 additions and 32 deletions

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@ -3,36 +3,6 @@
#include <sstream>
#include <stdexcept>
namespace {
// Fast 64-bit int power function
inline std::uint64_t Powuli(const std::uint64_t &b, const std::uint64_t &e) {
std::uint64_t buf = 1;
for (std::uint64_t i = 0; i < e; i++)
buf *= b;
return buf;
}
}
std::uint64_t GeneralUtility::BaseX_2_10(const std::string& num, const std::string& set) {
// If base is 0, throw logic error
if (set.length() == 0)
throw std::logic_error("Can't convert from base0! Please supply a nonempty set!");
unsigned long long int buf = 0;
for (std::size_t i = 0; i < num.length(); i++) {
for (std::size_t j = 0; j < set.length(); j++) {
if (num[i] == set[j]) {
buf += Powuli((std::uint64_t)set.length(), (uint64_t)(num.length() - (i + 1))) * j;
break;
}
}
}
return buf;
}
// Based on: https://www.geeksforgeeks.org/divide-large-number-represented-string/
std::pair<std::string, int>
GeneralUtility::StringDivision(const std::string& dividend, const unsigned int divisor, const std::string& set) {

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@ -27,7 +27,8 @@ public:
//! \param num A string representing the number
//! \param set The set/base of the number
//! \return A 64-bit integer representing the number
static std::uint64_t BaseX_2_10(const std::string& num, const std::string& set);
template <class T_Container>
static std::uint64_t BaseX_2_10(const T_Container& num, const T_Container& set);
//! Will convert a number to an arbitrary base.
//! This just a wrapper for BaseX_2_Y.
@ -49,6 +50,37 @@ private:
GeneralUtility();
};
namespace {
// Fast 64-bit int power function
inline std::uint64_t Powuli(const std::uint64_t &b, const std::uint64_t &e) {
std::uint64_t buf = 1;
for (std::uint64_t i = 0; i < e; i++)
buf *= b;
return buf;
}
}
template <class T_Container>
std::uint64_t GeneralUtility::BaseX_2_10(const T_Container& num, const T_Container& set) {
// If base is 0, throw logic error
if (set.size() == 0)
throw std::logic_error("Can't convert from base0! Please supply a nonempty set!");
unsigned long long int buf = 0;
for (std::size_t i = 0; i < num.size(); i++) {
for (std::size_t j = 0; j < set.size(); j++) {
if (num[i] == set[j]) {
buf += Powuli((std::uint64_t)set.size(), (uint64_t)(num.size() - (i + 1))) * j;
break;
}
}
}
return buf;
}
template<typename T_Type, class T_Container>
int GeneralUtility::Ord(const T_Type& item, const T_Container& set) {
const auto result =

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@ -65,6 +65,26 @@ TEST_CASE(__FILE__"/BaseFuckingBig_to_10", "[BaseX_2_10]")
TEST_CASE(__FILE__"/NoSetSupplied", "[BaseX_2_10]")
{
REQUIRE_THROWS_AS(
GeneralUtility::BaseX_2_10("699", "")
GeneralUtility::BaseX_2_10<std::string>("699", "")
, std::logic_error);
}
// Tests that conversion with more complex 'digits' works. Weird-ass usecase
TEST_CASE(__FILE__"/BaseWeird_to_10", "[BaseX_2_10]")
{
// Setup
// Yes... That is actually our base...
const std::vector<std::string> set = { "Banana", "Apple", "Peach", "Strawberry", "Tomato", "Cherry" };
// Yes, that is a fucking number. It's 69 in whatever the fuck that base is
const std::vector<std::string> in = { "Apple", "Cherry", "Strawberry" };
const std::uint64_t expected_out = 69;
// Exercise
const std::uint64_t out = GeneralUtility::BaseX_2_10(in, set);
// Verify
REQUIRE(out == expected_out);
}