---

s=open('8.txt').read()
k=0
l=0
m=0
zapr=0
for r in range(len(s)):
    if s[r-1]+s[r] in ['DS','SD'] and r>0:zapr +=1
    if s[r]=='D' : k+=1
    if s[r] in ['0123456789']:zapr+=1
    while zapr>0 or k>100:
        if s[r-1]+s[r] in ['DS','SD'] and r>0:zapr -=1
        if s[r]=='D' : k-=1
        if s[r] in ['0123456789']:zapr-=1
        l+=1
    m=max(r-l+1,m)
print(m)