First Non-Repeating Character Problem Statement

You are given a string consisting of English alphabet characters. Your task is to identify and return the first character in the string that does not repeat. If every character repeats, return the first character of the string.

Input:

T (the number of test cases)
For each test case, a string consisting of English alphabet characters ('a' - 'z' and 'A' - 'Z').

Output:

For each test case, print the first non-repeating character in the string.
If no such character exists, print the first character of the string.

Example:

Input:

1
abcdabc

Output:

d

Constraints:

• 1 ≤ T ≤ 10
• 1 ≤ Length of Input String ≤ 104

Note:

You do not need to print anything; implement the function only.