A piece of iron wire is used up half of it first, and then the remaining half is used to reduce 1 meter, and finally 5 meters are left. How many meters is this iron wire originally?
一根铁丝先用去它的一半，再用去剩下的一半少1米，最后剩下5米，这根铁丝原来长多少米？
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">4 * 2 * 2</gadget>
<output>16</output>

<result>16</result>