file = open('24_10724.txt')
A = list(map(str, file.readlines()))
A = ''.join(A)
A = list(A)
Max = 0
B = ''
for i in range(len(A)):
        if A[i] in ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E']:
                B += B.join(A[i])
                Max = max(Max, len(B))
        else:
                B = ''
print(Max)