--- id: a5229172f011153519423690 title: Sum All Odd Fibonacci Numbers isRequired: true challengeType: 5 --- ## Description <section id='description'> Given a positive integer <code>num</code>, return the sum of all odd Fibonacci numbers that are less than or equal to <code>num</code>. The first two numbers in the Fibonacci sequence are 1 and 1. Every additional number in the sequence is the sum of the two previous numbers. The first six numbers of the Fibonacci sequence are 1, 1, 2, 3, 5 and 8. For example, <code>sumFibs(10)</code> should return <code>10</code> because all odd Fibonacci numbers less than or equal to <code>10</code> are 1, 1, 3, and 5. Remember to use <a href='http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514' target='_blank'>Read-Search-Ask</a> if you get stuck. Try to pair program. Write your own code. </section> ## Instructions <section id='instructions'> </section> ## Tests <section id='tests'> ```yml tests: - text: <code>sumFibs(1)</code> should return a number. testString: assert(typeof sumFibs(1) === "number", '<code>sumFibs(1)</code> should return a number.'); - text: <code>sumFibs(1000)</code> should return 1785. testString: assert(sumFibs(1000) === 1785, '<code>sumFibs(1000)</code> should return 1785.'); - text: <code>sumFibs(4000000)</code> should return 4613732. testString: assert(sumFibs(4000000) === 4613732, '<code>sumFibs(4000000)</code> should return 4613732.'); - text: <code>sumFibs(4)</code> should return 5. testString: assert(sumFibs(4) === 5, '<code>sumFibs(4)</code> should return 5.'); - text: <code>sumFibs(75024)</code> should return 60696. testString: assert(sumFibs(75024) === 60696, '<code>sumFibs(75024)</code> should return 60696.'); - text: <code>sumFibs(75025)</code> should return 135721. testString: assert(sumFibs(75025) === 135721, '<code>sumFibs(75025)</code> should return 135721.'); ``` </section> ## Challenge Seed <section id='challengeSeed'> <div id='js-seed'> ```js function sumFibs(num) { return num; } sumFibs(4); ``` </div> </section> ## Solution <section id='solution'> ```js function sumFibs(num) { var a = 1; var b = 1; var s = 0; while (a <= num) { if (a % 2 !== 0) { s += a; } a = [b, b=b+a][0]; } return s; } ``` </section>