SRM597 Dic2 Medium

LittleElephantAndString.py

class LittleElephantAndString:
    def getNumber(self, A, B):
        if sorted(A) != sorted(B):
            return -1

        A = list(A)[::-1]
        B = list(B)[::-1]

        non_move = 0
        a_index = 0
        b_index = 0
        while(b_index < len(B) and a_index < len(A)):
            while(a_index < len(A)):
                if A[a_index] == B[b_index]:
                    non_move += 1
                    break
                a_index += 1
            b_index += 1
            a_index += 1

        return len(A) - non_move