diff --git a/cpp/prime-factors/CMakeLists.txt b/cpp/prime-factors/CMakeLists.txt new file mode 100644 index 0000000..56a3675 --- /dev/null +++ b/cpp/prime-factors/CMakeLists.txt @@ -0,0 +1,59 @@ +# Get the exercise name from the current directory +get_filename_component(exercise ${CMAKE_CURRENT_SOURCE_DIR} NAME) + +# Basic CMake project +cmake_minimum_required(VERSION 2.8.11) + +# Name the project after the exercise +project(${exercise} CXX) + +# Locate Boost libraries: unit_test_framework, date_time and regex +set(Boost_USE_STATIC_LIBS ON) +set(Boost_USE_MULTITHREADED ON) +set(Boost_USE_STATIC_RUNTIME OFF) +find_package(Boost 1.55 REQUIRED COMPONENTS unit_test_framework date_time regex) + +# Enable C++11 features on gcc/clang +if("${CMAKE_CXX_COMPILER_ID}" MATCHES "(GNU|Clang)") + set(CMAKE_CXX_FLAGS "-std=c++11") +endif() + +# Configure to run all the tests? +if(${EXERCISM_RUN_ALL_TESTS}) + add_definitions(-DEXERCISM_RUN_ALL_TESTS) +endif() + +# Get a source filename from the exercise name by replacing -'s with _'s +string(REPLACE "-" "_" file ${exercise}) + +# Implementation could be only a header +if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${file}.cpp) + set(exercise_cpp ${file}.cpp) +else() + set(exercise_cpp "") +endif() + +# Include a test helper header if it exists +if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/require_equal_containers.h) + set(test_helper require_equal_containers.h) +else() + set(test_helper "") +endif() + +# Build executable from sources and headers +add_executable(${exercise} ${file}_test.cpp ${test_helper} ${exercise_cpp} ${file}.h) + +# We need boost includes +target_include_directories(${exercise} PRIVATE ${Boost_INCLUDE_DIRS}) + +# We need boost libraries +target_link_libraries(${exercise} ${Boost_LIBRARIES}) + +# Tell MSVC not to warn us about unchecked iterators in debug builds +if(${MSVC}) + set_target_properties(${exercise} PROPERTIES + COMPILE_DEFINITIONS_DEBUG _SCL_SECURE_NO_WARNINGS) +endif() + +# Run the tests on every build +add_custom_command(TARGET ${exercise} POST_BUILD COMMAND ${exercise}) diff --git a/cpp/prime-factors/README.md b/cpp/prime-factors/README.md new file mode 100644 index 0000000..534aa21 --- /dev/null +++ b/cpp/prime-factors/README.md @@ -0,0 +1,65 @@ +# Prime Factors + +Compute the prime factors of a given natural number. + +A prime number is only evenly divisible by itself and 1. + +Note that 1 is not a prime number. + +## Example + +What are the prime factors of 60? + +- Our first divisor is 2. 2 goes into 60, leaving 30. +- 2 goes into 30, leaving 15. + - 2 doesn't go cleanly into 15. So let's move on to our next divisor, 3. +- 3 goes cleanly into 15, leaving 5. + - 3 does not go cleanly into 5. The next possible factor is 4. + - 4 does not go cleanly into 5. The next possible factor is 5. +- 5 does go cleanly into 5. +- We're left only with 1, so now, we're done. + +Our successful divisors in that computation represent the list of prime +factors of 60: 2, 2, 3, and 5. + +You can check this yourself: + +- 2 * 2 * 3 * 5 +- = 4 * 15 +- = 60 +- Success! + +## Getting Started + +Make sure you have read [the C++ page](http://exercism.io/languages/cpp) on +exercism.io. This covers the basic information on setting up the development +environment expected by the exercises. + +## Passing the Tests + +Get the first test compiling, linking and passing by following the [three +rules of test-driven development](http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd). +Create just enough structure by declaring namespaces, functions, classes, +etc., to satisfy any compiler errors and get the test to fail. Then write +just enough code to get the test to pass. Once you've done that, +uncomment the next test by moving the following line past the next test. + +```C++ +#if defined(EXERCISM_RUN_ALL_TESTS) +``` + +This may result in compile errors as new constructs may be invoked that +you haven't yet declared or defined. Again, fix the compile errors minimally +to get a failing test, then change the code minimally to pass the test, +refactor your implementation for readability and expressiveness and then +go on to the next test. + +Try to use standard C++11 facilities in preference to writing your own +low-level algorithms or facilities by hand. [CppReference](http://en.cppreference.com/) +is a wiki reference to the C++ language and standard library. If you +are new to C++, but have programmed in C, beware of +[C traps and pitfalls](http://www.slideshare.net/LegalizeAdulthood/c-traps-and-pitfalls-for-c-programmers). + +## Source + +The Prime Factors Kata by Uncle Bob [view source](http://butunclebob.com/ArticleS.UncleBob.ThePrimeFactorsKata) diff --git a/cpp/prime-factors/prime_factors_test.cpp b/cpp/prime-factors/prime_factors_test.cpp new file mode 100644 index 0000000..ea4b219 --- /dev/null +++ b/cpp/prime-factors/prime_factors_test.cpp @@ -0,0 +1,95 @@ +#include "prime_factors.h" +#define BOOST_TEST_MAIN +#include + +BOOST_AUTO_TEST_CASE(_1_yields_empty) +{ + const std::vector expected{}; + + const std::vector actual{prime_factors::of(1)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +#if defined(EXERCISM_RUN_ALL_TESTS) +BOOST_AUTO_TEST_CASE(_2_yields_2) +{ + const std::vector expected{2}; + + const std::vector actual{prime_factors::of(2)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_3_yields_3) +{ + const std::vector expected{3}; + + const std::vector actual{prime_factors::of(3)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_4_yields_2_2) +{ + const std::vector expected{2, 2}; + + const std::vector actual{prime_factors::of(4)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_6_yields_2_3) +{ + const std::vector expected{2, 3}; + + const std::vector actual{prime_factors::of(6)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_8_yields_2_2_2) +{ + const std::vector expected{2, 2, 2}; + + const std::vector actual{prime_factors::of(8)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_9_yields_3_3) +{ + const std::vector expected{3, 3}; + + const std::vector actual{prime_factors::of(9)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_27_yields_3_3_3) +{ + const std::vector expected{3, 3, 3}; + + const std::vector actual{prime_factors::of(27)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_625_yields_5_5_5_5) +{ + const std::vector expected{5, 5, 5, 5}; + + const std::vector actual{prime_factors::of(625)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} + +BOOST_AUTO_TEST_CASE(_901255_yields_5_17_23_461) +{ + const std::vector expected{5, 17, 23, 461}; + + const std::vector actual{prime_factors::of(901255)}; + + BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end()); +} +#endif