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Implement a Function to Check if a Number is a Palindrome

Certification: Intermediate Level Accuracy: 71.43% Submissions: 14 Points: 5

Write a Python function that determines whether a given number is a palindrome. A palindrome is a number that reads the same forwards and backwards.

Example 1
    
  
  • Input: 12321
    • 
  
  • Output: True
    • 
  
  • Explanation: 
    
      
      
    • Step 1: Take the input number 12321.
      • 
      
    • Step 2: Read the number from left to right: 12321.
      • 
      
    • Step 3: Read the number from right to left: 12321.
      • 
      
    • Step 4: Compare both readings and find they are identical.
      • 
      
    • Step 5: Return True as the result.
      • 
    
    
  
    •
Example 2
    
  
  • Input: 12345
    • 
  
  • Output: False
    • 
  
  • Explanation: 
    
      
      
    • Step 1: Take the input number 12345.
      • 
      
    • Step 2: Read the number from left to right: 12345.
      • 
      
    • Step 3: Read the number from right to left: 54321.
      • 
      
    • Step 4: Compare both readings and find they are different.
      • 
      
    • Step 5: Return False as the result.
      • 
    
    
  
    •
Constraints
    
  
  • -10^9 ≤ n ≤ 10^9
    • 
  
  • Return True if the number is a palindrome, False otherwise
    • 
  
  • Time Complexity: O(d), where d is the number of digits
    • 
  
  • Space Complexity: O(d) or O(1) depending on the approach
    •
StringsFunctions / MethodsCognizantCapgemini
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Hint
Solution

Solution Hints

    
  
  • Convert the number to a string and compare with its reverse: str(n) == str(n)[::-1]
    • 
  
  • Use mathematical operations to reverse the number without string conversion
    • 
  
  • Handle negative numbers: they cannot be palindromes due to the negative sign
    • 
  
  • For non-string approach: extract digits and rebuild the number in reverse
    •

Steps to solve by this approach:

 Step 1: Handle edge case: negative numbers cannot be palindromes

 Step 2: Convert the number to a string for easier manipulation

 Step 3: Create a reversed version of the string using slicing with [::-1]

 Step 4: Compare the original string with its reversed version

 Step 5: Return True if they are identical (palindrome)

 Step 6: Return False if they are different (not a palindrome)

 Step 7: Example: 12321 is a palindrome because "12321" == "12321"[::-1]

Submitted Code :