Reverse a string without affecting special characters

Given a string, that contains special character together with alphabets (a to z and A to Z), reverse the string in a way that special characters are not affected.

Input: str = "a,b$c"

Output: str = "c,b$a"

Note that $ and , are not moved anywhere. Only subsequence "abc" is reversed.

Input: str = "Ab,c,de!$"

Output: str = "ed,c,bA!$"

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class Main { //your main method public static void main(String[] args) { } // you will have to implement Utils class with its method reverseLetters

}

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public class Utils{ public static String reverseLetters(String word){ //your code here } }