Given a number ‘n’ and our goal is to find out it is palindrome or not without using
any extra space. We can’t make a new copy of number .
Input : 2332 Output : Yes it is Palindrome. Explanation: original number = 2332 reversed number = 2332 Both are same hence the number is palindrome. Input :1111 Output :Yes it is Palindrome. Input : 1234 Output : No not Palindrome.
A recursive solution is discussed in below post.
Check if a number is Palindrome
In this post a different solution is discussed.
1) We can compare the first digit and the last digit, then we repeat the process.
2) For the first digit, we need the order of the number. Say, 12321. Dividing this by 10000 would get us the leading 1. The trailing 1 can be retrieved by taking the mod with 10.
3 ) Now, to reduce this to 232.
(12321 % 10000)/10 = (2321)/10 = 232
4 ) And now, the 10000 would need to be reduced by a factor of 100.
Here is the implementation of the above algorithm :
Yes, it is Palindrome
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Improved By : jit_t