It takes two minutes to bake one cake (one minute for the front and one for the other side), and a maximum of two cakes can be placed in the pot at a time. How long does it take at least to bake five cakes?
烙一张饼需要两分钟(正反面各一分钟)，锅里每次最多可放两张饼，烙5张饼至少需要多少分钟．
<gadget id="calculator">1 * 3</gadget>
<output>3</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<result>5</result>