Python Coding: Linked List or String | Dataford Interview Questions

Write a Python function to reverse a linked list or find the first non-repeating character in a string.

For this task, implement first_non_repeating_char(s). Return the first character whose total frequency is one, or None if every character repeats. The input is a string, and character comparisons are case-sensitive.

Signature: def first_non_repeating_char(s):

Constraints

0 <= len(s) <= 10^5
The string may contain letters, digits, spaces, and punctuation
Character comparisons are case-sensitive

Function Signature

def first_non_repeating_char(s):

Your question is Python Coding: Linked List or String. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Write a Python function to reverse a linked list or find the first non-repeating character in a string.

Signature: def first_non_repeating_char(s):

Constraints

0 <= len(s) <= 10^5
The string may contain letters, digits, spaces, and punctuation
Character comparisons are case-sensitive

Function Signature

def first_non_repeating_char(s):

Your question is Python Coding: Linked List or String. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.