You are given a string s consisting only of first 20 lowercase Latin letters ('a', 'b', ..., 't').

Recall that the substring s[l; r] of the string s is the string s_l s_{l + 1} ... s_r. For example, the substrings of "codeforces" are "code", "force", "f", "for", but not "coder" and "top".

You can perform the following operation no more than once: choose some substring s[l; r] and reverse it (i.e. the string s_l s_{l + 1} ... s_r becomes s_r s_{r - 1} ... s_l).

Your goal is to maximize the length of the maximum substring of s consisting of distinct (i.e. unique) characters.

The string consists of distinct characters if no character in this string appears more than once. For example, strings "abcde", "arctg" and "minecraft" consist of distinct characters but strings "codeforces", "abacaba" do not consist of distinct characters.

Input

The only line of the input contains one string s consisting of no more than 10^6 characters 'a', 'b', ..., 't' (first 20 lowercase Latin letters).

Output

Print one integer — the maximum possible length of the maximum substring of s consisting of distinct characters after reversing no more than one its substring.

Examples

Input


abacaba


Output


3


Input


abcdecdf


Output


6


Input


aabbcc


Output


3


Input


abcdeefc


Output


6
/**
 * BaZ :D
 */

import java.lang.reflect.Array;
import java.util.*;
import java.io.*;
import static java.lang.Math.*;

public class Main
{
    static MyScanner scan;
    static PrintWriter pw;
    static long MOD = 1_000_000_007;
    static long INF = 1_000_000_000_000_000_000L;
    static long inf = 2_000_000_000;
    public static void main(String[] args) {
        new Thread(null, null, "BaZ", 1 << 27) {
            public void run() {
                try {
                    solve();
                } catch (Exception e) {
                    e.printStackTrace();
                    System.exit(1);
                }
            }
        }.start();
    }
    static boolean have[];
    static int dp[][], bc[];
    static void solve() throws IOException
    {
        //initIo(true);
        initIo(false);
        StringBuilder sb = new StringBuilder();
        char c[] = ne().toCharArray();
        int n = c.length;
        have =  new boolean[(1<<20)];
        for(int i=0;i<n;++i) {
            int mask = 0;
            for(int j=i;j<n;++j) {
                if((mask&(1<<(c[j] - 'a')))==0) {
                    mask|=(1<<(c[j] - 'a'));
                    have[mask]  = true;
                }
                else {
                    have[mask] = true;
                    break;
                }
            }
        }
        bc = new int[(1<<20)];
        for(int i=0;i<(1<<20);++i) {
            if(have[i]) {
                bc[i] = Integer.bitCount(i);
            }
        }
        dp = new int[(1<<20)][21];
        for(int i=0;i<(1<<20);++i) {
            dp[i][20] = bc[i];
        }
        for(int pos=19;pos>=0;--pos) {
            for(int i=0;i<(1<<20);++i) {
                if((i&(1<<pos))!=0) {
                    dp[i][pos] = dp[i^(1<<pos)][pos+1];
                }
                else {
                    dp[i][pos] = max(dp[i][pos+1], dp[i^(1<<pos)][pos+1]);
                }
            }
        }
        int ans = 0;
        for(int i=0;i<(1<<20);++i) {
            if(!have[i]) {
                continue;
            }
            //pl("len : "+Integer.bitCount(e));
            ans = max(ans, bc[i] + dp[i][0]);
        }
        //pl();
        pl(ans);
        pw.flush();
        pw.close();
    }
//    static int f(int mask, int pos) {
//        if(pos==20) {
//            if(have[mask]) {
//                return bc[mask];
//            }
//            else {
//                return 0;
//            }
//        }
//        if(dp[mask][pos]!=-1) {
//            return dp[mask][pos];
//        }
//        if((mask&(1<<pos))!=0) {
//            return dp[mask][pos] = f((mask^(1<<pos)), pos+1);
//        }
//        else {
//            return dp[mask][pos] = max(f(mask, pos+1), f(mask^(1<<pos), pos+1));
//        }
//    }
    static void initIo(boolean isFileIO) throws IOException {
        scan = new MyScanner(isFileIO);
        if(isFileIO) {
            pw = new PrintWriter("/Users/amandeep/Desktop/output.txt");
        }
        else {
            pw = new PrintWriter(System.out, true);
        }
    }
    static int ni() throws IOException
    {
        return scan.nextInt();
    }
    static long nl() throws IOException
    {
        return scan.nextLong();
    }
    static double nd() throws IOException
    {
        return scan.nextDouble();
    }
    static String ne() throws IOException
    {
        return scan.next();
    }
    static String nel() throws IOException
    {
        return scan.nextLine();
    }
    static void pl()
    {
        pw.println();
    }
    static void p(Object o)
    {
        pw.print(o+" ");
    }
    static void pl(Object o)
    {
        pw.println(o);
    }
    static void psb(StringBuilder sb)
    {
        pw.print(sb);
    }
    static void pa(String arrayName, Object arr[])
    {
        pl(arrayName+" : ");
        for(Object o : arr)
            p(o);
        pl();
    }
    static void pa(String arrayName, int arr[])
    {
        pl(arrayName+" : ");
        for(int o : arr)
            p(o);
        pl();
    }
    static void pa(String arrayName, long arr[])
    {
        pl(arrayName+" : ");
        for(long o : arr)
            p(o);
        pl();
    }
    static void pa(String arrayName, double arr[])
    {
        pl(arrayName+" : ");
        for(double o : arr)
            p(o);
        pl();
    }
    static void pa(String arrayName, char arr[])
    {
        pl(arrayName+" : ");
        for(char o : arr)
            p(o);
        pl();
    }
    static void pa(String listName, List list)
    {
        pl(listName+" : ");
        for(Object o : list)
            p(o);
        pl();
    }
    static void pa(String arrayName, Object[][] arr) {
        pl(arrayName+" : ");
        for(int i=0;i<arr.length;++i) {
            for(Object o : arr[i])
                p(o);
            pl();
        }
    }
    static void pa(String arrayName, int[][] arr) {
        pl(arrayName+" : ");
        for(int i=0;i<arr.length;++i) {
            for(int o : arr[i])
                p(o);
            pl();
        }
    }
    static void pa(String arrayName, long[][] arr) {
        pl(arrayName+" : ");
        for(int i=0;i<arr.length;++i) {
            for(long o : arr[i])
                p(o);
            pl();
        }
    }
    static void pa(String arrayName, char[][] arr) {
        pl(arrayName+" : ");
        for(int i=0;i<arr.length;++i) {
            for(char o : arr[i])
                p(o);
            pl();
        }
    }
    static void pa(String arrayName, double[][] arr) {
        pl(arrayName+" : ");
        for(int i=0;i<arr.length;++i) {
            for(double o : arr[i])
                p(o);
            pl();
        }
    }
    static class MyScanner
    {
        BufferedReader br;
        StringTokenizer st;
        MyScanner(boolean readingFromFile) throws IOException
        {
            if(readingFromFile) {
                br = new BufferedReader(new FileReader("/Users/amandeep/Desktop/input.txt"));
            }
            else {
                br = new BufferedReader(new InputStreamReader(System.in));
            }
        }
        String nextLine()throws IOException
        {
            return br.readLine();
        }
        String next() throws IOException
        {
            if(st==null || !st.hasMoreTokens())
                st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }
        int nextInt() throws IOException
        {
            return Integer.parseInt(next());
        }
        long nextLong() throws IOException
        {
            return Long.parseLong(next());
        }
        double nextDouble() throws IOException
        {
            return Double.parseDouble(next());
        }
    }
}