Description

Xiao Ming is learning about lexicographical sorting and wants to study the internal structure of stable sorting. He defines a cost as the absolute difference between a character's index before sorting and its index after sorting. Given a string, when sorted lexicographically in ascending order, Xiao Ming calculates the total cost of this stable sort by summing up all the costs. Please design a program to calculate the total cost of this stable sort.

Input Format

The input consists of $1$ line: containing a string $S$, where the string length $len$ ($1≤len≤1000$).

Output Format

The output consists of $1$ line, containing $1$ number representing the total cost of the stable lexicographical sort of the string.

Sample

chuan

8