leetcode-javascript

1. Largest Number

　　For example, given [3, 30, 34, 5, 9], the largest formed number is 9534330.

　

// wrong answer
var largestNumber = function(nums) {
    var str = nums.join().replace(/\,/g, '');
    var arr = [];
    for(var i = 0; i > str.length; i++) {
        arr.push(str.charAt[i]);
    }
    nums = arr.sort(function(a, b) {
        return a - b;
    })
    return nums;
};

// right answer
var largestNumber2 = function(nums) {

    if(nums.length < 1) return 'error!'

    if(nums.length === 1) return nums[0]

    nums.sort(function(a, b) {
        return '' + a + b < '' + b + a
    })

    return nums.join().replace(/\,/g, '');
};