|Educational Codeforces Round 32|
You are given a string s consisting of lowercase Latin letters. Character c is called k-dominant iff each substring of s with length at least k contains this character c.
You have to find minimum k such that there exists at least one k-dominant character.
The first line contains string s consisting of lowercase Latin letters (1 ≤ |s| ≤ 100000).
Print one number — the minimum value of k such that there exists at least one k-dominant character.