When Ma Xiaole did an integer subtraction problem, he regarded the 1 in the unit digit of the subtrahend as 7, and the 3 in the tens digit of the subtrahend as 5, and the resulting difference was 123. What should be the correct result?
马小乐做一道整数减法题时，把减数个位上的1看成7，把减数十位上的3看成5，结果得出的差是123．正确的结果应该是多少？
<gadget id="calculator">57 + 123</gadget>
<output>180</output>

<gadget id="calculator">180 - 31</gadget>
<output>149</output>

<result>149</result>