运行以下代码，正确的打印结果是？（ ）

def f(s):

t=0

max=0

for i in s:

    if i>="0" and i<="9":

        t=t+1

    else:

        if t>max:

            max=t

        t=0

print(max)

list="123ab45cd6d"

f(list)