345. Reverse Vowels of a String

Problem Statement

Given a string s, reverse only all the vowels in the string and return it.

The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in both lower and upper cases, more than once.

Examples

Example 1:

• Input: s = "hello"
• Output: "holle"

Example 2:

• Input: s = "leetcode"
• Output: "leotcede"

Constraints:

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

Solution

var vowels = map[rune]bool{
	'a': true,
	'e': true,
	'i': true,
	'o': true,
	'u': true,
	'A': true,
	'E': true,
	'I': true,
	'O': true,
	'U': true,
}

func reverseVowels(s string) string {
	b := []rune(s)
	l, r := 0, len(b)-1
	for l < r {
		if vowels[b[l]] {
			if vowels[b[r]] {
				b[l], b[r] = b[r], b[l]
                l++
                r--
			}else{
                r--
            }
		}else{
            l++
        }
	}
	return string(b)
}