What are some common coding interview questions?

What are some common coding interview questions I should prepare for?

Some common coding interview questions include:

1. Reverse a string.
2. Find the first non-repeating character in a string.
3. Merge two sorted arrays.
4. Implement a binary search.
5. Check if a string is a palindrome.

Can you explain how to reverse a string in Python?

Sure! You can reverse a string in Python using slicing:

reversed_string = original_string[::-1]

This creates a new string that is the reverse of original_string.

What about finding the first non-repeating character?

To find the first non-repeating character, you can use a dictionary to count occurrences:

def first_non_repeating_char(s):
    char_count = {}
    for char in s:
        char_count[char] = char_count.get(char, 0) + 1
    for char in s:
        if char_count[char] == 1:
            return char
    return None