Given a string of size ‘n’. The task is to remove or delete minimum number of characters from the string so that the resultant string is palindrome.
Note: The order of characters should be maintained.
Input : aebcbda Output : 2 Remove characters 'e' and 'd' Resultant string will be 'abcba' which is a palindromic string Input : geeksforgeeks Output : 8
A simple solution is to remove all subsequences one by one and check if remaining string is palindrome or not. Time complexity of this solution is exponential.
An efficient approach uses the concept of finding the length of the longest palindromic subsequence of a given sequence.
-->str is the given string. -->n length of str -->len be the length of the longest palindromic subsequence of str -->// minimum number of deletions min = n - len
Minimum number of deletions = 8
Time Complexity : O(n2)
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