Reverse Vowels of a String

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Given a string s, reverse only all the vowels in the string and return it.The vowels are 'a', 'e', 'i', 'o', 'u', and they can appear in both lower and upper cases.Other characters should remain in their original positions.

Example 1

Input

[
  "hello"
]

Output

holle

Explanation. The vowels are 'e' and 'o'. Reversing them swaps their positions: 'o' takes 'e''s place, and 'e' takes 'o''s place.

Example 2

Input

[
  "leetcode"
]

Output

leotcede

Explanation. The vowels are 'e' (at index 1), 'e' (at index 4), 'o' (at index 5), 'e' (at index 7). After reversing only these vowels, 'e' (original index 7) goes to index 1, 'o' (original index 5) goes to index 4, 'e' (original index 4) goes to index 5, and 'e' (original index 1) goes to index 7.

Example 3

Input

[
  "aA"
]

Output

Explanation. The vowels are 'a' and 'A'. Reversing them results in 'A' then 'a'.

Example 4

Input

[
  "aeiou"
]

Output

uoiea

Explanation. All characters are vowels. Reversing the entire string of vowels results in 'u', 'o', 'i', 'e', 'a'.

Example 5

Input

[
  "rhythm"
]

Output

rhythm

Explanation. There are no vowels in the string 'rhythm', so the string remains unchanged.

Example 6

Input

[
  "DesignPatterns"
]

Output

DesagnPitterNs

Explanation. Vowels are 'e','i','a','e','a','e'. Reversed: 'e','a','e','a','i','e'. The string becomes DesagnPitterNs

Follow-up: Can you solve this problem with O(1) extra space complexity, assuming the input string is mutable (e.g., convertible to a character array)?

Constraints:

1. `1 <= s.length <= 3 * 10^5`2. `s` consists of printable ASCII characters.

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