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Palindromes And Indexes

Difficulty: MEDIUM
Contributed By
Hardik Aggarwal
Avg. time to solve
50 min
Success Rate
44%

Problem Statement

You are given a string S consisting of lowercase characters only, an index ‘i’ and length ‘len’. Your task is to find the count of all palindromic substrings in the string ‘S’ which start at index ‘i’ and have a length of at least ‘len’.

A string is called palindromic if it reads the same backward as forward. ex "aba" is a palindrome but "abaab" is not a palindrome.

Note: A substring is a contiguous non-empty segment of the string.

For example:
String S = ababa
Index i = 1
len = 3

The answer to the above test case is 2 since there are two substrings that start at index 1 (1 - based indexing) - “aba”, “ababa”. Both these have a length of at least 3.
Input Format:
The first line contains a single integer ‘T’ denoting the number of test cases to be run. Then the test cases follow.

The first line of each test case contains the string S.

The next line contains 2 space-separated integers denoting index ‘i’ and length ‘len’.
Output Format:
For each test case, print an integer denoting the number of possible strings.

Output for each test case will be printed in a separate line.
Note:
You are not required to print anything; it has already been taken care of. Just implement the function.
Constraints:
1 <= T <= 10
1 <= |S| <= 10^4
1 <= i, len <= N

Time Limit: 1 sec.
Sample Input 1:
2
ababa
1 3
abaaa
2 2
Sample Output 1:
2
0
Explanation For Sample Output 1:
For the first test case aba, ababa are the two palindromic substrings.

For the second test case there are no palindromic substrings of length greater than 2 beginning with 2nd index.
Sample Input 2:
2
aaaaa
3 1
abc
3 3
Sample Output 2:
3
0
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