BinaryGapCodility.js

function solution(N) {
	// write your code in JavaScript (Node.js 8.9.4)
	if (N === parseInt(N, 10) && N >= 1 && N <= 2147483647) {
		const binaryArray = N.toString(2).split('');
		let res = 0;
		let acc = 0;
		binaryArray.forEach((el, i, arr) => {
			if (el === '0' && arr[i - 1] === '1') {
				acc++;
			}
			else if (el === '0' && acc) {
				acc++;
			}
			else if (el === '1') {
				if (acc > res) {
					res = acc;
				}
				acc = 0;
			}
		});
		return res;
	}
	return 0;
}