Check if Number is Even or Odd

1. The Challenge: Even or Odd Determination

Create a function is_even_or_odd(num) that takes an integer and returns "even" if the number is even, and "odd" if the number is odd.

2. Why It Matters

Determining even/odd numbers is a classic algorithmic building block used in grid layouts, zebra striping table rows, and partitioning list elements.

3. The Python Solution

Check if num % 2 == 0 using an if/else conditional:

def is_even_or_odd(num):
    if num % 2 == 0:
        return "even"
    else:
        return "odd"

# Alternative 1-liner using Python Ternary Expression
def is_even_or_odd_fast(num):
    return "even" if num % 2 == 0 else "odd"

# Testing our function
print(is_even_or_odd(3))  # Output: "odd"
print(is_even_or_odd(14)) # Output: "even"
print(is_even_or_odd(0))  # Output: "even"

4. Python Ternary Syntax

Python uses value_if_true if condition else value_if_false for inline 1-line conditional assignments.

5. Common Mistakes

• Forgetting Zero: Zero is an even number (0 % 2 == 0 is True). Ensure your logic correctly identifies 0 as even!

6. Next Steps

Use ternary expressions for clean 1-line returns. Next, let's retrieve the first element of a list!