C++ numbers

.github/workflows/cpp.yml

@@ -29,7 +29,7 @@ jobs:
           # Check if the files are present in the changed file list (added, modified, deleted) then output to stdout.
           HAS_DIFF=false
           printf "=== Which C++ files changed? ===\n"
-          if printf "%s\n" "${GIT_DIFF}" | grep -E '^(.*[.](cpp|h|hpp)|.*/[Ma]akefile|.github/workflows/cpp.yml)$'; then
+          if printf "%s\n" "${GIT_DIFF}" | grep -E '^(.*[.](cpp|h|hpp)|.*/[Ma]akefile|.*/CMakeLists.txt|.github/workflows/cpp.yml)$'; then
             HAS_DIFF=true
           fi
           printf "\n"

cpp/README.md

@@ -26,3 +26,5 @@
 - [reverse-string](./reverse-string/README.md)
 - [armstrong-numbers](./armstrong-numbers/README.md)
 - [bob](./bob/README.md)
+- [difference-of-squares](./difference-of-squares/README.md)
+- [luhn](./luhn/README.md)

cpp/darts/darts.cpp

@@ -2,8 +2,9 @@
 
 namespace darts {
 
+// NOLINTNEXTLINE(readability-identifier-length)
 int score(double x, double y) {
-    double distance = std::hypot(x, y);
+    const double distance = std::hypot(x, y);
 
     if (distance <= 1.0) {
         return 10;

cpp/darts/darts.hpp

@@ -5,7 +5,7 @@
 
 namespace darts {
 
-    int score(double x, double y);
+    int score(double x, double y); // NOLINT(readability-identifier-length)
 
 } // namespace darts
 

cpp/darts/run-tests-cpp.txt

@@ -6,9 +6,9 @@ Running automated test file(s):
 Running: make clean
 rm -rf ./build
 
-real	0m0.006s
-user	0m0.002s
-sys	0m0.004s
+real	0m0.017s
+user	0m0.003s
+sys	0m0.014s
 
 ===============================================================================
 
@@ -78,17 +78,17 @@ TOTAL                                         68      63    92%
 lines: 92.6% (63 out of 68)
 branches: 38.6% (85 out of 220)
 
-real	0m10.058s
-user	0m9.218s
-sys	0m0.835s
+real	0m9.722s
+user	0m8.891s
+sys	0m0.827s
 
 ===============================================================================
 
 cmake-format --in-place CMakeLists.txt
 
-real	0m0.157s
-user	0m0.111s
-sys	0m0.048s
+real	0m0.144s
+user	0m0.107s
+sys	0m0.038s
 
 ===============================================================================
 
@@ -110,66 +110,50 @@ found lint:
   Convention: 4
 
 
-real	0m0.161s
-user	0m0.121s
-sys	0m0.041s
+real	0m0.169s
+user	0m0.123s
+sys	0m0.046s
 
 ===============================================================================
 
 Running: clang-format-16 -style=file -i ./darts.cpp ./darts_test.cpp
 
-real	0m0.022s
-user	0m0.010s
+real	0m0.018s
+user	0m0.006s
 sys	0m0.012s
 
 ===============================================================================
 
 Running: ../../.github/citools/cpp/clang-check
 clang-check-16 --analyze ./darts.cpp ./darts_test.cpp ./darts.hpp
 
-real	0m0.553s
-user	0m0.517s
-sys	0m0.036s
+real	0m0.555s
+user	0m0.526s
+sys	0m0.029s
 
 
-real	0m0.555s
-user	0m0.519s
-sys	0m0.036s
+real	0m0.557s
+user	0m0.526s
+sys	0m0.031s
 
 ===============================================================================
 
 Running: ../../.github/citools/cpp/clang-tidy | head -n 100
-8744 warnings generated.
-44098 warnings generated.
-52839 warnings generated.
-Suppressed 52839 warnings (52834 in non-user code, 5 NOLINT).
+8739 warnings generated.
+44091 warnings generated.
+52830 warnings generated.
+Suppressed 52843 warnings (52830 in non-user code, 13 NOLINT).
 Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
 
-real	0m8.772s
-user	0m8.698s
-sys	0m0.074s
-Running: clang-tidy-16 ./darts.cpp ./darts_test.cpp ./darts.hpp
-/home/vpayno/git_vpayno/exercism-workspace/cpp/darts/darts.cpp:5:18: warning: parameter name 'x' is too short, expected at least 3 characters [readability-identifier-length]
-int score(double x, double y) {
-                 ^
-/home/vpayno/git_vpayno/exercism-workspace/cpp/darts/darts.cpp:5:28: warning: parameter name 'y' is too short, expected at least 3 characters [readability-identifier-length]
-int score(double x, double y) {
-                           ^
-/home/vpayno/git_vpayno/exercism-workspace/cpp/darts/darts.cpp:6:5: warning: variable 'distance' of type 'double' can be declared 'const' [misc-const-correctness]
-    double distance = std::hypot(x, y);
-    ^
-           const 
-/home/vpayno/git_vpayno/exercism-workspace/cpp/darts/darts.hpp:8:22: warning: parameter name 'x' is too short, expected at least 3 characters [readability-identifier-length]
-    int score(double x, double y);
-                     ^
-/home/vpayno/git_vpayno/exercism-workspace/cpp/darts/darts.hpp:8:32: warning: parameter name 'y' is too short, expected at least 3 characters [readability-identifier-length]
-    int score(double x, double y);
-                               ^
-
-
-real	0m8.774s
-user	0m8.699s
+real	0m8.648s
+user	0m8.571s
 sys	0m0.076s
+Running: clang-tidy-16 ./darts.cpp ./darts_test.cpp ./darts.hpp
+
+
+real	0m8.650s
+user	0m8.571s
+sys	0m0.079s
 
 ===============================================================================
 

cpp/difference-of-squares/.exercism/config.json

@@ -0,0 +1,30 @@
+{
+  "authors": [
+    "LegalizeAdulthood"
+  ],
+  "contributors": [
+    "cyborgsphinx",
+    "elyashiv",
+    "jackhughesweb",
+    "KevinWMatthews",
+    "kytrinyx",
+    "patricksjackson",
+    "Scientifica96"
+  ],
+  "files": {
+    "solution": [
+      "difference_of_squares.cpp",
+      "difference_of_squares.h"
+    ],
+    "test": [
+      "difference_of_squares_test.cpp"
+    ],
+    "example": [
+      ".meta/example.cpp",
+      ".meta/example.h"
+    ]
+  },
+  "blurb": "Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.",
+  "source": "Problem 6 at Project Euler",
+  "source_url": "http://projecteuler.net/problem=6"
+}

cpp/difference-of-squares/.exercism/metadata.json

@@ -0,0 +1 @@
+{"track":"cpp","exercise":"difference-of-squares","id":"1d6ee9dc443a4708a1986d9c1d94f29d","url":"https://exercism.org/tracks/cpp/exercises/difference-of-squares","handle":"vpayno","is_requester":true,"auto_approve":false}

cpp/difference-of-squares/CMakeLists.txt

@@ -0,0 +1,68 @@
+# Get the exercise name from the current directory
+get_filename_component(exercise ${CMAKE_CURRENT_SOURCE_DIR} NAME)
+
+# Basic CMake project
+cmake_minimum_required(VERSION 3.5.1)
+
+# Name the project after the exercise
+project(${exercise} CXX)
+
+# 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 ${file}.cpp)
+else()
+  set(exercise_cpp "")
+endif()
+
+# Use the common Catch library?
+if(EXERCISM_COMMON_CATCH)
+  # For Exercism track development only
+  add_executable(${exercise} ${file}_test.cpp ${exercise_cpp} ${file}.hpp
+                             $<TARGET_OBJECTS:catchlib>)
+elseif(EXERCISM_TEST_SUITE)
+  # The Exercism test suite is being run, the Docker image already includes a
+  # pre-built version of Catch.
+  find_package(Catch2 REQUIRED)
+  add_executable(${exercise} ${file}_test.cpp ${exercise_cpp} ${file}.hpp)
+  target_link_libraries(${exercise} PRIVATE Catch2::Catch2WithMain)
+  # When Catch is installed system wide we need to include a different header,
+  # we need this define to use the correct one.
+  target_compile_definitions(${exercise} PRIVATE EXERCISM_TEST_SUITE)
+else()
+  # Build executable from sources and headers
+  add_executable(${exercise} ${file}_test.cpp ${exercise_cpp} ${file}.hpp
+                             test/tests-main.cpp)
+endif()
+
+set_target_properties(
+  ${exercise}
+  PROPERTIES CXX_STANDARD 17
+             CXX_STANDARD_REQUIRED OFF
+             CXX_EXTENSIONS OFF)
+
+set(CMAKE_BUILD_TYPE Debug)
+
+if("${CMAKE_CXX_COMPILER_ID}" MATCHES "(GNU|Clang)")
+  set_target_properties(
+    ${exercise} PROPERTIES COMPILE_FLAGS "-Wall -Wextra -Wpedantic -Werror")
+endif()
+
+# Configure to run all the tests?
+if(${EXERCISM_RUN_ALL_TESTS})
+  target_compile_definitions(${exercise} PRIVATE EXERCISM_RUN_ALL_TESTS)
+endif()
+
+# Tell MSVC not to warn us about unchecked iterators in debug builds
+if(${MSVC})
+  set_target_properties(${exercise} PROPERTIES COMPILE_DEFINITIONS_DEBUG
+                                               _SCL_SECURE_NO_WARNINGS)
+endif()
+
+# Run the tests on every build
+add_custom_target(
+  test_${exercise} ALL
+  DEPENDS ${exercise}
+  COMMAND ${exercise})

cpp/difference-of-squares/HELP.md

@@ -0,0 +1,55 @@
+# Help
+
+## Running the tests
+
+Running the tests involves running `cmake -G` and then using the build command appropriate for your platform.
+Detailed instructions on how to do this can be found on the [Running the Tests](https://exercism.io/tracks/cpp/tests) page for C++ on exercism.io.
+
+## 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.
+
+## Submitting your solution
+
+You can submit your solution using the `exercism submit difference_of_squares.cpp difference_of_squares.h` command.
+This command will upload your solution to the Exercism website and print the solution page's URL.
+
+It's possible to submit an incomplete solution which allows you to:
+
+- See how others have completed the exercise
+- Request help from a mentor
+
+## Need to get help?
+
+If you'd like help solving the exercise, check the following pages:
+
+- The [C++ track's documentation](https://exercism.org/docs/tracks/cpp)
+- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5)
+- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
+
+Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
+
+To get help if you're having trouble, you can use one of the following resources:
+
+- [`c++-faq` tag on StackOverflow](https://stackoverflow.com/tags/c%2b%2b-faq/info)
+- [C++ FAQ from isocpp.com](https://isocpp.org/faq)
+- [CppReference](http://en.cppreference.com/) is a wiki reference to the C++ language and standard library
+- [C traps and pitfalls](http://www.slideshare.net/LegalizeAdulthood/c-traps-and-pitfalls-for-c-programmers) is useful if you are new to C++, but have programmed in C

cpp/difference-of-squares/Makefile

@@ -0,0 +1,23 @@
+.PHONY: clean
+clean:
+	rm -rf ./build
+
+.PHONY: test
+test: clean
+	mkdir -pv ./build
+
+	@printf "\n"
+	@# each line is executed in a subshell, we have to daisy chain them so they
+	@# run in the build directory
+	cd ./build; export LDFLAGS="-lgcov --coverage" CXXFLAGS="--coverage"; cmake -DEXERCISM_RUN_ALL_TESTS=1 -DCMAKE_EXPORT_COMPILE_COMMANDS=1 -G 'Unix Makefiles' ../; if make; then printf "\n=== All Tests Passed ===\n"; else printf "\n=== Test Failure ===\n"; false; fi
+
+.PHONY: coverage
+coverage: test
+	@printf "\n"
+	find . -regextype posix-egrep -regex "^.*(tests-main|CompilerId).*[.](gcda|gcno)$$" -print -delete
+
+	@printf "\n"
+	find . -regextype posix-egrep -regex "^.*[.](gcda|gcno)12186"
+
+	@printf "\n"
+	gcovr --print-summary

cpp/difference-of-squares/README.md

@@ -0,0 +1,46 @@
+# Difference of Squares
+
+Welcome to Difference of Squares on Exercism's C++ Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.
+
+The square of the sum of the first ten natural numbers is
+(1 + 2 + ... + 10)² = 55² = 3025.
+
+The sum of the squares of the first ten natural numbers is
+1² + 2² + ... + 10² = 385.
+
+Hence the difference between the square of the sum of the first
+ten natural numbers and the sum of the squares of the first ten
+natural numbers is 3025 - 385 = 2640.
+
+You are not expected to discover an efficient solution to this yourself from first principles; research is allowed, indeed, encouraged.
+Finding the best algorithm for the problem is a key skill in software engineering.
+
+## Source
+
+### Created by
+
+- @LegalizeAdulthood
+
+### Contributed to by
+
+- @cyborgsphinx
+- @elyashiv
+- @jackhughesweb
+- @KevinWMatthews
+- @kytrinyx
+- @patricksjackson
+- @Scientifica96
+
+### Based on
+
+Problem 6 at Project Euler - http://projecteuler.net/problem=6
+
+### My Solution
+
+- [my solution]()
+- [run-tests](./run-tests-cpp.txt)