<p>下面代码的输出结果是( )<br/> a = [[1,2,3], [4,5,6], [7,8,9]]<br/> s = 0 for c in a:<br/> for j in range(3):<br/> s += c[j]<br/> print(s)</p>
<p> 0 </p>
<p> 45 </p>
<p> 以上答案都不对 </p>
<p> 24</p>
