686. 重复叠加字符串匹配

class Solution(object):
    def repeatedStringMatch(self, A, B):
        """
        :type A: str
        :type B: str
        :rtype: int
        """
        lenb = len(B)
        # 用来暂存原A串
        temp = A
        for i in range(1, int((lenb * 2) / (len(temp))) + 3):
            # 重复叠加A串
            A = temp * i
            # B串若是A的子串，则A串长度大于B串
            if len(A) < lenb:
                continue
            if B in A:
                return i
        return -1