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Check if a Number is a Palindrome

Certification: Basic Level Accuracy: 69.23% Submissions: 13 Points: 10

Write a C++ function to check if a given integer is a palindrome. A palindrome number reads the same backward as forward.

Example 1
    
  
  • Input: number = 121
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  • Output: true
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  • Explanation:
    
      
      
    • Step 1: Read the number from right to left.
      • 
      
    • Step 2: Compare with the original number.
      • 
      
    • Step 3: Since both are the same, return true.
      • 
    
    
  
    •
Example 2
    
  
  • Input: number = 123
    • 
  
  • Output: false
    • 
  
  • Explanation:
    
      
      
    • Step 1: Read the number from right to left, which gives 321.
      • 
      
    • Step 2: Compare with the original number 123.
      • 
      
    • Step 3: Since they are different, return false.
      • 
    
    
  
    •
Constraints
    
  
  • -2^31 ≤ number ≤ 2^31 - 1
    • 
  
  • Time Complexity: O(n), where n is the number of digits in the number
    • 
  
  • Space Complexity: O(1)
    •
NumberControl StructuresTech MahindraeBay
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Hint
Solution

Solution Hints

    
  
  • Convert the number to a string and compare it with its reverse.
    • 
  
  • Use arithmetic operations to reverse the number and compare it with the original number.
    • 
  
  • Handle negative numbers separately since they cannot be palindromes.
    •

Steps to solve by this approach:

 Step 1: Define a function is_palindrome that takes an integer number.
 Step 2: Handle edge case: negative numbers cannot be palindromes.
 Step 3: Initialize variables for the reversed number and the original number.
 Step 4: Reverse the number by extracting digits from right to left.
 Step 5: Compare the reversed number with the original number.
 Step 6: Return true if they match, false otherwise.
 Step 7: In main, call is_palindrome with a number and print the result.

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