sieve: initial commit

This commit is contained in:
Dmitry Kokorin 2016-03-31 11:23:28 +03:00
parent 2e77b43e48
commit 14bf87c43f
3 changed files with 159 additions and 0 deletions

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cpp/sieve/CMakeLists.txt Normal file
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# 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})

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cpp/sieve/README.md Normal file
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# Sieve
Write a program that uses the Sieve of Eratosthenes to find all the primes from 2 up to a given number.
The Sieve of Eratosthenes is a simple, ancient algorithm for finding all
prime numbers up to any given limit. It does so by iteratively marking as
composite (i.e. not prime) the multiples of each prime,
starting with the multiples of 2.
Create your range, starting at two and continuing up to and including the given limit. (i.e. [2, limit])
The algorithm consists of repeating the following over and over:
- take the next available unmarked number in your list (it is prime)
- mark all the multiples of that number (they are not prime)
Repeat until you have processed each number in your range.
When the algorithm terminates, all the numbers in the list that have not
been marked are prime.
The wikipedia article has a useful graphic that explains the algorithm:
https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
Notice that this is a very specific algorithm, and the tests don't check
that you've implemented the algorithm, only that you've come up with the
correct list of primes.
## Getting Started
Make sure you have read the [getting started with C++](http://help.exercism.io/getting-started-with-cpp.html)
page on the [exercism help site](http://help.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
Sieve of Eratosthenes at Wikipedia [view source](http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes)

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cpp/sieve/sieve_test.cpp Normal file
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#include "sieve.h"
#define BOOST_TEST_MAIN
#include <boost/test/unit_test.hpp>
BOOST_AUTO_TEST_CASE(primes_up_to_10)
{
const std::vector<int> expected{2, 3, 5, 7};
const std::vector<int> actual = sieve::primes(10);
BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end());
}
#if defined(EXERCISM_RUN_ALL_TESTS)
BOOST_AUTO_TEST_CASE(primes_up_to_1000)
{
const std::vector<int> expected{
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59,
61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131,
137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197,
199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271,
277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353,
359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433,
439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 503, 509,
521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601,
607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677,
683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769,
773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859,
863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953,
967, 971, 977, 983, 991, 997
};
const std::vector<int> actual = sieve::primes(1000);
BOOST_REQUIRE_EQUAL_COLLECTIONS(expected.begin(), expected.end(), actual.begin(), actual.end());
}
#endif