How many small cubes are needed to assemble some cubes with side lengths of 1 cm into a large cube with side lengths of 4 cm.
把一些棱长是1厘米的正方体拼成一个棱长是4厘米的大正方体，至少需要多少个小正方体．
<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<gadget id="calculator">4 * 4 * 4</gadget>
<output>64</output>

<result>64</result>