**Time limit:**1.00 s**Memory limit:**512 MB

*special*if every character that appears in the string appears the same number of times in the substring.

Your task is to count the number of special substrings in a given string.

**Input**

The only input line has a string of length $n$. Every character is between a...z.

**Output**

Print one integer: the number of special substrings.

**Constraints**

- $1 \le n \le 2 \cdot 10^5$

**Example**

Input:

`abccabab`

Output:

`5`

Explanation: The special substrings are

`abc`

, `cab`

, `abccab`

, `bccaba`

and `ccabab`

.