const fibonacci = function(number) { if (number == 0) { return 0; } if (number < 0) { return "OOPS"; } let a = 1, b = 1; let sum = a; for (let i = 0; i < number - 2; i++, (i % 2 == 0) ? a = sum : b = sum) { sum = a + b; } return sum; }; // Do not edit below this line module.exports = fibonacci;