Problem11241--ABC375 - D - ABA

11241: ABC375 - D - ABA

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

You are given a string $S$ consisting of uppercase English letters.
Find the number of integer triples $(i, j, k)$ satisfying both of the following conditions:
  • $1 \leq i < j < k \leq |S|$
  • The length-$3$ string formed by concatenating $S_i$, $S_j$, and $S_k$ in this order is a palindrome.
Here, $|S|$ denotes the length of $S$, and $S_x$ denotes the $x$-th character of $S$.

Input

The input is given from Standard Input in the following format:
$S$

Output

Print the answer.

Constraints

  • $S$ is a string of length between $1$ and $2 \times 10^5$, inclusive, consisting of uppercase English letters.

Sample 1 Input

ABCACC

Sample 1 Output

5
The triples satisfying the conditions are $(i, j, k) = (1, 2, 4), (1, 3, 4), (3, 4, 5), (3, 4, 6), (3, 5, 6)$.

Sample 2 Input

OOOOOOOO

Sample 2 Output

56

Sample 3 Input

XYYXYYXYXXX

Sample 3 Output

75

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