Largest Number

Given a list of non negative integers, arrange them such that they form the largest number. For example, given [3, 30, 34, 5, 9], the largest formed number is 9534330.

• Time: O(nlogn)
• Space: O(1)

public String largestNumber(int[] nums) {
    String[] strs = new String[nums.length];
    for (int i = 0; i < nums.length; i++) {
        strs[i] = String.valueOf(nums[i]);
    }
    Arrays.sort(strs, new Comparator<String>() {
        @Override
        public int compare(String s1, String s2) {
            return s1.concat(s2).compareTo(s2.concat(s1));
        }
    });
    if (strs[strs.length - 1].equals("0")) {
        return "0";
    }
    StringBuilder sb = new StringBuilder();
    for (int i = nums.length - 1; i >= 0; i--) {
        sb.append(strs[i]);
    }
    return sb.toString();
}