When Xiaohu was doing a subtraction problem, he wrote 9 by mistake in the ones digit of the subtrahend, and 1 by mistake in the 7 digits in the subtraction. The final difference was 577. What is the correct answer to this question?
小虎做一道减法题时，把被减数个位上的6错写成了9，减数十位上的7错写成了1，最后所得的差是577，这道题的正确答案是多少．
<gadget id="calculator">70 - 10</gadget>
<output>60</output>

<gadget id="calculator">9 - 6</gadget>
<output>3</output>

<gadget id="calculator">60 + 3</gadget>
<output>63</output>

<gadget id="calculator">577 - 63</gadget>
<output>514</output>

<result>514</result>