777+777-777*777/777=how many.
777+777-777*777/777=多少．
<gadget id="calculator">777 / 777</gadget>
<output>1</output>

<gadget id="calculator">777 * 1</gadget>
<output>777</output>

<gadget id="calculator">777 - 777</gadget>
<output>0</output>

<gadget id="calculator">777 + 0</gadget>
<output>777</output>

<result>777</result>