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()
d={}
for i in range(len(s)):
    if(s[i] not in d):
        d[s[i]]=1
    else:
        d[s[i]]+=1
l=[]
ma=0
for c,i in d.items():
    if(ma<i):
        ma=i
if(ma==1):
    print(len(s))
else:
    for c,i in d.items():
        if(i==ma):
            l.append(c)
    ans=len(s)
    for i in range(len(l)):
        ma=0
        prev=0
        
        for j in range(0,len(s)):
            if(s[j]==l[i]):
                if(ma<(j+1-prev)):
                    ma=j+1-prev
                prev=j+1
        if(ma<(len(s)+1-prev)):
            ma=len(s)+1-prev
        if(ans>ma):
            ans=ma
    print(ans)