four-digit number, use it to subtract the number on each digit in turn, the result is still a four-digit number, the final result is known to be 346A, what is the number A?
一个四位数，用它依次减去它的各个数位上的数字，得到的结果仍是一个四位数，已知最后结果为346A，求数字A是多少？
<result>5</result>