Given a non-negative number up to 10 digits long, find the largest number that can be formed with the digits and is divisible by 3. If no number can be formed that is divisible by 3, return 0.
Input: int Output int
Examples:
- largest_div_by_three(0) -> 0
- largest_div_by_three(24) -> 42
- largest_div_by_three(319) -> 93
- largest_div_by_three(113) -> 3
- largest_div_by_three(111) -> 111