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, '');
 };