codility - binary gap

codility-binary-gap.js

function solution(N) {
    // write your code in JavaScript (Node.js 8.9.4)
    //100100001001
    const binaryValue = N.toString(2);
    
    let start = false;
    let count = 0;
    let greater = 0;
    
    for (let i in binaryValue) {
        let bit = binaryValue[i];
        if (bit === '1') {
            if (start) {
                greater = greater < count ? count : greater;
                count = 0;
            } else {
                start = true;
            }
        } else {
            if (start) {
                count = count + 1;
            } 
        }
    }
    
    return greater;
}