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).
none
abacaba
2
zzzzz
1
abcde
3
bcaccacaaabaacaabaaabcbbcbcaacacbcbaaaacccacbbcbaabcbacaacbabacacacaccbbccbcbacbbbbccccabcabaaab
8
daabcdabbabbacacbaacabacbcaabaacac
4
abghim
4
gfliflgfhhdkceacdljgkegmdlhcgkcmlelmbbbmdddgdeeljjhgbbffmemmmkhebgkhadkdajabcjkcgbkgbaeacdedlkklfech
17
a
1
aaabbb
4
ab
2
abbb
2
ob
2
abccba
3
saaaaaaaas
2
axxx
2
abcba
2
abb
2
abcdea
4
axcbb
3
tmivvdcbbfrfogjviirrximhttoskopwrcmkcborcxvr
13
dlchmmuateksgldkckljrovmeuniobjrelqjpnjljlvhpqrjsfklliqpufplgaelevmlcnodbllquubobecem
15
zx
2
zxz
2
bbhdgaefbhf
6
xx
1
zxx
2
cbcada
4
z
1
aab
2
jficc
3
cceeaabfba
5
jk
2
lzeznbwu
5
rr
1
s=input()
se=set(s)
if len(se)==len(s):
    print((len(s)//2)+1)
elif len(se)==1:
    print(1)
else:
    dif={}
    d={}
    for index,i in enumerate(s):
        if d.get(i,[])!=[]:
            if len(d[i])>=2:
                dif[i]=max(index-d[i][-1],dif[i])
            else:
                dif[i] =index - d[i][-1]
            d[i].append(index)

        else:
            d[i]=[]
            d[i].append(index)
            dif[i]=index+1
    need=sorted(d.keys(),key=lambda k:dif[k],reverse=False)
    req=True
    num = (len(s) // 2) + 1
    for i in need:
        if len(d[i])>=(len(s)//dif[i]) and dif[i]<=num:
            print(dif[i])
            req=False
            break
    if req:
        print(num)

