IOIPALIN - Palindrome 2000
A palindrome is a symmetrical string, that is, a string read identically from left to right as well as from right to left. You are to write a program which, given a string, determines the minimal number of characters to be inserted into the string in order to obtain a palindrome. As an example, by inserting 2 characters, the string "Ab3bd" can be transformed into a palindrome ("dAb3bAd" or "Adb3bdA"). However, inserting fewer than 2 characters does not produce a palindrome.
Input
The first line contains one integer: the length of the input string N, 3 ≤ N ≤ 5000. The second line contains one string with length N. The string is formed from uppercase letters from ‘A’ to ‘Z’, lowercase letters from ‘a’ to ‘z’ and digits from ‘0’ to ‘9’. Uppercase and lowercase letters are to be considered distinct.
Output
The first line contains one integer, which is the desired minimal number.
Example
Input: 5 Ab3bd Output: 2
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sneh sajal:
2015-12-18 23:36:49
try to optimize space in linear :) |
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janina:
2015-12-18 18:42:37
O(n^2) space O(n^2) time and scanf,printf will give you AC. |
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rakhejabhai:
2015-12-09 19:46:28
linear space is the key to AC |
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LEMONICE:
2015-10-23 07:00:25
I am not able to submit! It says Error,Wrong problem code! |
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Shubham Garg:
2015-10-03 07:52:48
Use faster method for string input. No space optimization is required.But space optimization does give lower time. Last edit: 2015-10-03 08:07:29 |
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ashish:
2015-09-25 20:27:54
no space optimisation is required.
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Mauro Persano:
2015-07-28 17:00:58
No spoilers, please! |
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no name:
2015-07-03 19:16:21
just removed function call overhead, without doing any space or any optimization at all. AC :O
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Carlos Vinícios:
2015-06-14 10:01:26
I got AC without any space optimization. |
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Ankit:
2015-06-09 19:04:57
nice que ,AC in one go:) Last edit: 2015-06-09 19:05:37 |
Added by: | Gareev |
Date: | 2010-08-16 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: NODEJS OBJC PERL6 VB.NET |
Resource: | IOI 2000, Day 1 |