If it takes 1 minute to saw a piece of wood into 2 pieces, how many minutes will it take to saw it into 5 pieces?
把一根木头锯成两段需要1分钟，如果把它锯成5段需要多少分钟．
<gadget id="calculator">2 - 1</gadget>
<output>1</output>

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

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

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

<result>4</result>