Problem:
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: serval → srvvl → svvv → vvv.

Sample Input 2

jackal

Sample Output 2

2

One solution is: jackal → aacaa → aaaa.

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.

Solution in C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Text;
using System.Collections.Generic;
using System.Collections;
using static System.Math;
using System.Linq;
using static System.Array;

namespace ConsoleApp2
{
    class Program
    {
        static string S;
        static void Main(string[] args)
        {
            //N = long.Parse(Console.ReadLine());
            //var NM = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
            S = Console.ReadLine();
            long ans = S.Length;
            for (char moji = 'a'; moji <= 'z'; ++moji)
            {
                ans = Min(ans,Cul(moji));
            }
            Console.WriteLine(ans);
        }
       
        static long Cul(char spi)
        {
            var tmp = S.Split(spi).ToArray();
            long ans = 0;
            foreach (var item in tmp)
            {
                ans = Max(ans, item.Length);
            }
            return ans;
        }
    }


}