PALIN - The Next Palindrome

A positive integer is called a palindrome if its representation in the decimal system is the same when read from left to right and from right to left. For a given positive integer K of not more than 1000000 digits, write the value of the smallest palindrome larger than K to output. Numbers are always displayed without leading zeros.


The first line contains integer t, the number of test cases. Integers K are given in the next t lines.


For each K, output the smallest palindrome larger than K.




Warning: large Input/Output data, be careful with certain languages

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sharingancoder: 2018-02-18 07:28:23

can someone give some corner cases where code can go wrong

Last edit: 2018-02-18 08:11:07
adilmah: 2018-01-25 14:39:15

@quock The constraint is given on the number of digits

shashankpathak: 2018-01-25 10:20:38

I want to ask that if we have to find just preceding palindrome of the number then what should be the approach

quock: 2018-01-23 08:19:38

Here description say K can not be larger than 1000000 but the test cases assert also a big int
11111111111111111111211111111111111111111. Is it expecting case to cover ?

hrk27071999: 2018-01-15 19:39:46

can someone give me corner cases for this code that is easy to mistake?

jonmanu: 2018-01-15 19:18:32

I got TLE in this program. How should i fix this?

rswetabh_1995: 2018-01-15 08:57:29

Last edit: 2018-01-15 08:59:30
bashnewbie: 2018-01-08 15:34:46

Nice problem ;)

If you analyse well enough you will find that there are many corner cases that will take care of themselves

anna_9701: 2018-01-07 12:18:31

akash9827 Long int is too short to handle such long number as ~1000000 digits...

akash9827: 2018-01-06 05:32:10

I did this by reversing the number , i've checked corner cases too , all are correct.
but then too i'm getting wrong answer.
NOTE---->>> I've taken input as "unsigned long int", do i need to take input as a string and then do the processing??

Added by:adrian
Time limit:2s-9s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL6

Problem's scores 1 vote

Concept difficulty
Concept difficulty 38%
Implementation difficulty
Implementation difficulty 49%
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