You are given a positive integer?num?consisting only of digits?6?and?9.

Return?the maximum number you can get by changing?at most?one digit (6?becomes?9, and?9?becomes?6).

?

Example 1:

Input: num = 9669Output: 9969Explanation: Changing the first digit results in 6669. Changing the second digit results in 9969. Changing the third digit results in 9699. Changing the fourth digit results in 9666. The maximum number is 9969.

Example 2:

Input: num = 9996Output: 9999Explanation: Changing the last digit 6 to 9 results in the maximum number.

Example 3:

Input: num = 9999Output: 9999Explanation: It is better not to apply any change.

?

Constraints:

• 1 <= num <= 104

• num?consists of only?6?and?9?digits.

找到第一個是6的數(shù)字，將這個數(shù)字轉化為9就可以了，

Runtime2 ms

Beats

40.65%

Memory41.4 MB

Beats

18.55%