solve(nums) — nums holds non-negative integers. Arrange them so that, written one
after the other, they form the largest possible number. Return it as a string
(the result can be far too big for a number).
Sorting by value or alphabetically does not work: "34" + "3" = 343 beats"3" + "34" = 334, so 34 goes before 3. Sort with a custom comparator
instead: a goes before b when a + b is larger than b + a as strings.
If the result starts with 0 every number was zero — return "0".
Examples
solve([10,2]) → "210"
solve([3,30,34,5,9]) → "9534330"
solve([0,0]) → "0"Sample tests