Navigating the Loop: Advanced Tips

This approach beautifully sidesteps non-alphabetical characters. But let's talk about the "how" for a moment. To ensure accuracy, remember to iterate the reversedAlpha array independently from the loop that scans the original string.

Optional: Simplifying with .shift()

If the thought of juggling another pointer or index leaves you dizzy, here's a simpler alternative: use the .shift() method. This function efficiently grabs the left-most element in an array, essentially doing the pointer's job for you. Imagine it as having a helper who hands you each reversed "gold coin" as you walk along your original path.

Method 2: The Two-Pointer Skip Technique

Method 2

Dual Pointers with a Twist

The second approach also involves using two pointers, much like our first method. However, this one comes with a twist: it skips over the non-alphabetical characters directly.

How to Skip Efficiently

Just like in a dance, when a couple realizes they are out of sync, they adjust their steps. Similarly, if either of the pointers encounters a non-alphabetical character, it simply "dances" past it, without making a swap.

By adopting this approach, you get to keep the original sequence of non-alphabetical characters intact while reversing only the alphabets. Think of it as flipping some tiles on a mosaic floor without disturbing the overall pattern.

1package main
2
3import (
4	"fmt"
5	"unicode"
6)
7
8func isAlpha(c rune) bool {
9	return unicode.IsLetter(c)
10}
11
12func swap(arr []rune, a int, b int) {
13	t := arr[a]
14	arr[a] = arr[b]
15	arr[b] = t
16}
17
18func reverseOnlyAlphabetical(s string) string {
19	arr := []rune(s)
20	left := 0
21	right := len(arr) - 1
22
23	for left < right {
24		if !isAlpha(arr[left]) {
25			left++
26		} else if !isAlpha(arr[right]) {
27			right--
28		} else {
29			swap(arr, left, right)
30			left++
31			right--
32		}
33	}
34	return string(arr)
35}
36
37func main() {
38	fmt.Println(reverseOnlyAlphabetical("sea!$hells3"))
39}