Maximize the Canonical Concatenation of Integer Spellings
Company: Amazon
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Other
### Problem
Arrange all given nonnegative integers so that concatenating their ordinary decimal spellings forms the largest possible number. Return that number as a string, since it may exceed integer range. If all values are zero, represent the number as "0".
```cpp
string largestNumber(vector<int>& nums);
```
### Examples
```text
Input: nums = [12,121,9]
Output: "912121"
```
```text
Input: nums = [0,0,0]
Output: "0"
```
### Constraints
- Length is between 1 and 100.
- Each value is between 0 and 1000000000, inclusive.
- Use every input occurrence; the result is the largest concatenated number, not a list of chosen indices.
Overview: Build the largest canonical decimal concatenation with a transitive pairwise string-order comparator.
