The teaching building has 6 floors, each floor has 3 classrooms, and each classroom has 4 windows. How many windows are there in the whole building?
教学楼共有6层，每层有3间教室，每间教室有4扇窗子，整栋楼一共有多少扇窗子？
<gadget id="calculator">4 * 3 * 6</gadget>
<output>72</output>

<result>72</result>