Envío 5810

Código

my_str = input()

length =  len(my_str)

border_length = 0
counter = 0
i = length - 1

while i > 0:
    if my_str[i] == my_str[0]:
        j = i
        k = 0

        while j < length:
            if my_str[j] == my_str[k]:
                counter += 1
            else:
                counter = 0
                break
            j += 1
            k += 1

        if counter:
            border_length = counter
            counter = 0
    i -= 1

print(border_length)