Simple calculation: ((2001*2001+2001)/(2002*2002-2002)).
简算：((2001*2001+2001)/(2002*2002-2002))．
<gadget id="calculator">2_001 * 2_001</gadget>
<output>4_004_001</output>

<gadget id="calculator">4_004_001 + 2_001</gadget>
<output>4_006_002</output>

<gadget id="calculator">2_002 * 2_002</gadget>
<output>4_008_004</output>

<gadget id="calculator">4_008_004 - 2_002</gadget>
<output>4_006_002</output>

<gadget id="calculator">4_006_002 / 4_006_002</gadget>
<output>1</output>

<result>1</result>