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.

Input

The first line contains string s consisting of lowercase Latin letters (1 ≤ |s| ≤ 100000).

Output

Print one number — the minimum value of k such that there exists at least one k-dominant character.

Examples

Input

abacaba


Output

2


Input

zzzzz


Output

1


Input

abcde


Output

3
/**
 * Created by Khoi on 09/11/2017
 * For learning purpose
 */

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.*;


public class main {
    InputStream is;
    PrintWriter out;
    String INPUT;
    int[] dist = new int[26];
    int[] pos = new int[26];
    int min = 999999;
    void solve() {
        String s = ns();
        //int k = BSearch(1, s.length() / 2 + 1, s);
        for (int i = 0; i < s.length(); i++) {
            int c = s.charAt(i) - 'a';
            int new_dist = (i + 1) - pos[c];
            if (new_dist > dist[c]) {
                dist[c] = new_dist;
            }
            pos[c] = i + 1;
        }
        for (int i = 0; i < 26; i++) {
            int new_dist = s.length() + 1 - pos[i];
            if (dist[i] < new_dist)
                dist[i] = new_dist;
            if (dist[i] < min)
                min = dist[i];
        }
        out.println(min);
    }

    int BSearch(int low, int high, String s) {
        while (low < high) {
            int mid = (low + high) / 2;
            Set<Character> set = new HashSet<>();
            for (int i = 0; i < mid; i++)
                set.add(s.charAt(i));

            for (int i = 1; i < s.length() - mid + 1; i++) {
                String sub = s.substring(i, i + mid);
                Iterator<Character> itor = set.iterator();
                while (itor.hasNext()) {
                    char c = itor.next();
                    if (sub.indexOf(c) == -1) {
                        itor.remove();
                    }
                }
                if (set.isEmpty()) {
                    low = mid + 1;
                    break;
                }
            }
            if (!set.isEmpty()) {
                high = mid;
            }
        }
        return low;
    }

    void run() throws Exception {
        is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
        out = new PrintWriter(System.out);

        long s = System.currentTimeMillis();
        solve();
        out.flush();
        tr(System.currentTimeMillis() - s + "ms");
    }

    public static void main(String[] args) throws Exception {
        new main().run();
    }

    private byte[] inbuf = new byte[1024];
    public int lenbuf = 0, ptrbuf = 0;

    private int readByte() {
        if (lenbuf == -1) throw new InputMismatchException();
        if (ptrbuf >= lenbuf) {
            ptrbuf = 0;
            try {
                lenbuf = is.read(inbuf);
            } catch (IOException e) {
                throw new InputMismatchException();
            }
            if (lenbuf <= 0) return -1;
        }
        return inbuf[ptrbuf++];
    }


    private boolean isSpaceChar(int c) {
        return !(c >= 33 && c <= 126);
    }

    private boolean isEndLine(int c) {
        return c < 32;
    }

    private int skip() {
        int b;
        while ((b = readByte()) != -1 && isSpaceChar(b)) ;
        return b;
    }

    private double nd() {
        return Double.parseDouble(ns());
    }

    private char nc() {
        return (char) skip();
    }

    private String nsl() {
        int b = skip();
        StringBuilder sb = new StringBuilder();
        while (!(isEndLine(b))) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    private String ns() {
        int b = skip();
        StringBuilder sb = new StringBuilder();
        while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b != ' ')
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }

    private char[] ns(int n) {
        char[] buf = new char[n];
        int b = skip(), p = 0;
        while (p < n && !(isSpaceChar(b))) {
            buf[p++] = (char) b;
            b = readByte();
        }
        return n == p ? buf : Arrays.copyOf(buf, p);
    }

    private char[][] nm(int n, int m) {
        char[][] map = new char[n][];
        for (int i = 0; i < n; i++) map[i] = ns(m);
        return map;
    }

    private int[] na(int n) {
        int[] a = new int[n];
        for (int i = 0; i < n; i++) a[i] = ni();
        return a;
    }

    private int ni() {
        int num = 0, b;
        boolean minus = false;
        while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ;
        if (b == '-') {
            minus = true;
            b = readByte();
        }

        while (true) {
            if (b >= '0' && b <= '9') {
                num = num * 10 + (b - '0');
            } else {
                return minus ? -num : num;
            }
            b = readByte();
        }
    }

    private long nl() {
        long num = 0;
        int b;
        boolean minus = false;
        while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ;
        if (b == '-') {
            minus = true;
            b = readByte();
        }

        while (true) {
            if (b >= '0' && b <= '9') {
                num = num * 10 + (b - '0');
            } else {
                return minus ? -num : num;
            }
            b = readByte();
        }
    }

    // private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
    private boolean oj = true;

    private void tr(Object... o) {
        if (!oj) System.out.println(Arrays.deepToString(o));
    }
}