# Sum Of Multiples Given a number, find the sum of all the multiples of particular numbers up to but not including that number. If we list all the natural numbers up to but not including 20 that are multiples of either 3 or 5, we get 3, 5, 6 and 9, 10, 12, 15, and 18. The sum of these multiples is 78. Given a number, find the sum of the multiples of a given set of numbers, up to but not including that number. ## 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 A variation on Problem 1 at Project Euler [http://projecteuler.net/problem=1](http://projecteuler.net/problem=1) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.