Check if a string is Colindrome in Python

A colindrome is a special type of string that consists of concatenated palindromes, each exactly 6 characters long. To check if a string is a colindrome, we need to verify that its length is divisible by 6 and that each 6-character segment is a palindrome.

For example, the string "aabbaamnoonm" is a colindrome because it contains two 6-character palindromes: "aabbaa" and "mnoonm".

Algorithm

To solve this problem, we follow these steps:

• Check if the string length is divisible by 6
• Divide the string into 6-character segments
• Verify each segment is a palindrome
• Return True only if all segments are palindromes

Implementation

Here's the complete solution using a helper function to check palindromes:

def is_palindrome(s):
    return s == s[::-1]

def is_colindrome(s):
    # Check if length is divisible by 6
    if len(s) % 6 != 0:
        return False
    
    # Check each 6-character segment
    for i in range(0, len(s), 6):
        segment = s[i:i+6]
        if not is_palindrome(segment):
            return False
    
    return True

# Test with example
s = "aabbaamnoonm"
print(f"'{s}' is colindrome: {is_colindrome(s)}")

# Test segments individually
print(f"First segment 'aabbaa': {is_palindrome('aabbaa')}")
print(f"Second segment 'mnoonm': {is_palindrome('mnoonm')}")

'aabbaamnoonm' is colindrome: True
First segment 'aabbaa': True
Second segment 'mnoonm': True

Testing with Different Examples

Let's test the function with various inputs to understand its behavior:

def is_palindrome(s):
    return s == s[::-1]

def is_colindrome(s):
    if len(s) % 6 != 0:
        return False
    
    for i in range(0, len(s), 6):
        if not is_palindrome(s[i:i+6]):
            return False
    
    return True

# Test cases
test_strings = [
    "aabbaamnoonm",    # Valid colindrome
    "abccbadefged",    # Invalid - second segment not palindrome
    "abcdef",          # Invalid - not palindrome
    "racecar",         # Invalid - length not divisible by 6
    "abccbaxyzyx"      # Valid colindrome
]

for test in test_strings:
    result = is_colindrome(test)
    print(f"'{test}' -> {result}")

'aabbaamnoonm' -> True
'abccbadefged' -> False
'abcdef' -> False
'racecar' -> False
'abccbaxyzyx' -> True

How It Works

The algorithm works by:

1. Length Check: First verifying the string length is divisible by 6
2. Segmentation: Using range(0, len(s), 6) to iterate through 6-character chunks
3. Palindrome Verification: Checking each segment using string slicing s[::-1]
4. Early Return: Returning False immediately if any segment fails the palindrome test

Time and Space Complexity

• Time Complexity: O(n), where n is the length of the string
• Space Complexity: O(1), using constant extra space

Conclusion

A colindrome is a string composed of 6-character palindromes concatenated together. The solution efficiently checks length divisibility and validates each segment, making it suitable for strings of any valid colindrome length.