class Problem0203:
    def solve(this):
        s = list(input() + input())

        cnt = 0
        res = 0
        for c in s:
            cnt += 1
            if c == 'x':
                cnt = 0
            res = max(res, cnt)
        print(res)
if __name__ == "__main__":
    problem = Problem0203()
    problem.solve()