You are given a string $s$, consisting of only lowercase letters from a to z.

A pair of adjacent characters in the string is considered nice if and only if the two characters are adjacent in alphabet.
For example, ab, dc, xy are nice pairs while ll, ac and oi are not.

Your task is to find the number of nice pairs in $s$.

For example, in the string abcede, ab,bc,ed and de are nice pairs. Therefore the answer for this string is $4$.

Input

The only line consists of a string $s$ of lower case letters. ($1 \le \lvert s \rvert \le 100$)

Output

Output a single integer indicating the number of nice pairs of the string.