A calculator designed by Xiaoming has only one function key. Press the first time to subtract 19, press the second time to add 17, press the third time to subtract 19, and the fourth time to add 17... Now input a number is In 2003, please press the function key continuously, at least how many times, the calculator will display 0.
小明设计的一台计算器，只有一个功能键，按第一次完成减19，按第二次是加17，按第三次又减19，第四次又加17…，现在输入一个数是2003，请你连续地按功能键，至少按到第多少次后，计算器显示为0．
<gadget id="calculator">2_003 - 19</gadget>
<output>1_984</output>

<gadget id="calculator">19 - 17</gadget>
<output>2</output>

<gadget id="calculator">1_984 / 2</gadget>
<output>992</output>

<gadget id="calculator">992 * 2</gadget>
<output>1_984</output>

<gadget id="calculator">1_984 + 1</gadget>
<output>1_985</output>

<result>1_985</result>