670. Maximum Swap

Given a non-negative integer, you could swap two digits at most once to get the maximum valued number. Return the maximum valued number you could get.

Example 1:

Input: 2736
Output: 7236
Explanation: Swap the number 2 and the number 7.


Example 2:

Input: 9973
Output: 9973
Explanation: No swap.


Note:

1. The given number is in the range [0, 108]

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