[Algorithm] 13 week(4.04 ~ 4.10) 1/3

2220. Minimum Bit Flips to Convert Number

var minBitFlips = function(start, goal) {
    let startNum = start.toString(2);
    let goalNum = goal.toString(2);
    
    if (startNum.length > goalNum.length) {
       const missed = '0'.repeat(startNum.length - goalNum.length)
       goalNum = missed + goalNum;
    } else {
        const missed = '0'.repeat(goalNum.length - startNum.length)
        startNum = missed + startNum;
    }
    
    let count = 0
    
    for (let i = startNum.length - 1; i >= 0; i--) {
        if (startNum[i] !== goalNum[i]) count++
    }
    
    return count;
};