# Home

Score : $300$ points

### Problem Statement

Snuke can change a string $t$ of length $N$ into a string $t'$ of length $N - 1$ under the following rule:

• For each $i$ ($1 ≤ i ≤ N - 1$), the $i$-th character of $t'$ must be either the $i$-th or $(i + 1)$-th character of $t$.

There is a string $s$ consisting of lowercase English letters. Snuke's objective is to apply the above operation to $s$ repeatedly so that all the characters in $s$ are the same. Find the minimum necessary number of operations.

### Constraints

• $1 ≤ |s| ≤ 100$
• $s$ consists of lowercase English letters.

### Input

Input is given from Standard Input in the following format:

$s$


### Output

Print the minimum necessary number of operations to achieve the objective.

### Sample Input 1

serval


### Sample Output 1

3


One solution is: servalsrvvlsvvvvvv.

### Sample Input 2

jackal


### Sample Output 2

2


One solution is: jackalaacaaaaaa.

### Sample Input 3

zzz


### Sample Output 3

0


All the characters in $s$ are the same from the beginning.

### Sample Input 4

whbrjpjyhsrywlqjxdbrbaomnw


### Sample Output 4

8


In $8$ operations, he can change $s$ to rrrrrrrrrrrrrrrrrr.