s = input()
i1 = ""
flag = 0
i2 = 0
L=0
for i in range(len(s)):
    if i1 == "":
        if s[i] == "c":
            i1=i
    else:
        if s[i] == "w":
            if flag == 1:
                i2 = i
                if L < i2-i1+1:
                    L=i2-i1+1
                flag=0
                i1=""
                i2=0
            else:
                flag = 1
if L==0:
    L=-1
print(L)