Print Even - Odd in Python (Time Complexity: O(n))

Given a positive integer n, for each number from 0 to n - 1, print "odd" if the number is odd or the number itself if it is even.

Example:

Input: n = 6
Output (console):
0
odd
2
odd
4
odd

Note:

You have to print to the console, your function shouldn't return anything.

Understanding the Problem

The core challenge of this problem is to iterate through a range of numbers and determine whether each number is odd or even. If the number is odd, we print "odd"; if it is even, we print the number itself. This problem is straightforward but helps in understanding basic control structures and conditional statements in Python.

Approach

To solve this problem, we can use a simple loop to iterate through the numbers from 0 to n-1. For each number, we check if it is odd or even using the modulus operator (%). If the number is odd (i.e., number % 2 != 0), we print "odd". Otherwise, we print the number itself.

Naive Solution

The naive solution involves iterating through each number and using an if-else statement to check if the number is odd or even. This approach is already optimal for this problem since it runs in O(n) time complexity, where n is the input number.

Optimized Solution

Given the simplicity of the problem, the naive solution is already optimal. There are no further optimizations needed for this specific problem.

Algorithm

Start a loop from 0 to n-1.
For each number, check if it is odd or even using the modulus operator (%).
If the number is odd, print "odd".
If the number is even, print the number itself.

Code Implementation

def print_even_odd(n):
    # Iterate through each number from 0 to n-1
    for i in range(n):
        # Check if the number is odd
        if i % 2 != 0:
            print("odd")
        else:
            print(i)

# Example usage
n = 6
print_even_odd(n)

Complexity Analysis

The time complexity of this solution is O(n) because we are iterating through each number from 0 to n-1 exactly once. The space complexity is O(1) as we are not using any additional space that scales with the input size.

Edge Cases

Some potential edge cases include:

n = 1: The output should be "0".
n = 0: There should be no output as the range is empty.

These edge cases are handled naturally by the loop and conditional statements.

Testing

To test the solution comprehensively, consider the following test cases:

n = 6: Should print 0, odd, 2, odd, 4, odd.
n = 1: Should print 0.
n = 0: Should print nothing.
n = 10: Should print 0, odd, 2, odd, 4, odd, 6, odd, 8, odd.

Thinking and Problem-Solving Tips

When approaching such problems, it's important to:

Understand the problem statement clearly.
Break down the problem into smaller, manageable parts.
Think about edge cases and how to handle them.
Write clean and readable code with comments.

Conclusion

In this blog post, we discussed how to solve the problem of printing "odd" for odd numbers and the number itself for even numbers within a given range. We covered the problem definition, approach, algorithm, code implementation, complexity analysis, edge cases, and testing. Understanding and solving such problems helps in building a strong foundation in programming and problem-solving skills.

Additional Resources

For further reading and practice, consider the following resources: