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Check if a Number is a Palindrome

Certification: Basic Level Accuracy: 66.67% Submissions: 3 Points: 5

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

Example 1
    
  
  • Input: x = 121
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  • Output: true
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  • Explanation: 
      
      
    • Step 1: Check if the number is negative. It's not, so continue.
      • 
      
    • Step 2: Convert the integer to a string "121".
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    • Step 3: Compare characters from both ends of the string, moving inward.
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    • Step 4: All characters match, so the number is a palindrome.
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Example 2
    
  
  • Input: x = -121
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  • Output: false
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  • Explanation: 
      
      
    • Step 1: Check if the number is negative. It is, so it cannot be a palindrome due to the negative sign.
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    • Step 2: Return false immediately as negative numbers can't be palindromes.
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Constraints
    
  
  • The input is a 32-bit signed integer
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  • Time Complexity: O(log n) where n is the input number
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  • Space Complexity: O(1)
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NumberControl StructuresIBMZomato
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Hint
Solution

Solution Hints

    
  
  • Consider edge cases like negative numbers and zero.
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  • You can convert the number to a string for easier comparison.
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  • Alternatively, you can reverse the number by constructing a new integer.
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  • Be careful about integer overflow when reversing.
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  • Compare the reversed number with the original.
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Steps to solve by this approach:

 Step 1: Check if the number is negative. If yes, return false as it cannot be a  palindrome.
 Step 2: Convert the integer to a string for easier comparison.
 Step 3: Initialize two pointers, one at the beginning and one at the end of the string.
 Step 4: Compare characters from both ends while moving the pointers inward.
 Step 5: If any pair of characters doesn't match, return false. Otherwise, return true.

Submitted Code :