Today I have done leetcode's September LeetCoding Challenge with cpp.

September LeetCoding Challenge 18

Description

Largest Number

Given a list of non-negative integers nums, arrange them such that they form the largest number and return it.

Since the result may be very large, so you need to return a string instead of an integer.

Example 1:

Input: nums = [10,2]
Output: "210"

Example 2:

Input: nums = [3,30,34,5,9]
Output: "9534330"

Constraints:

• 1 <= nums.length <= 100
• 0 <= nums[i] <= 109

Solution

class Solution {
public:
  string largestNumber(vector<int>& nums) {
    string ans = "";
    sort(nums.begin(), nums.end(), [](int a, int b){
      return to_string(a)+to_string(b)>to_string(b)+to_string(a);
    });
    for(auto i : nums){
      ans += to_string(i);
    }
    return ans[0] == '0' ? "0" : ans;
  }
};