Given two strings A and B, find the minimum number of times A has to be repeated such that B is a substring of it. If no such solution, return -1.

For example, with A = "abcd" and B = "cdabcdab".

Return 3, because by repeating A three times (“abcdabcdabcd”), B is a substring of it; and B is not a substring of A repeated two times ("abcdabcd").

Note:
The length ofAandBwill be between 1 and 10000.

class Solution {
    public int repeatedStringMatch(String A, String B) {
        int count = 1;

        StringBuilder sb = new StringBuilder(A);
        for (; sb.length() < B.length(); count++){
            sb.append(A);
        }

        if (sb.toString().indexOf(B) >= 0) return count;
        if (sb.append(A).toString().indexOf(B) >= 0) return count + 1;

        return -1;
    }
}