擅长:python、mysql、java
<p>您应该考虑这样做(请记住这是伪代码):</p>
<pre><code>group1 = {m1, m2, m3}
group2 = {m4, m5}
group3 = {m6, m7, m8, m9}
len1 = group1.size
len2 = group2.size
len3 = group3.size
max = max(len1, len2, len3)
combination = {}
for i from 0 to max:
combination = {}
if(group1(i) exists)
combination.add(group1(i))
else combination.add("null")
if(group2(i) exists)
combination.add(group2(i))
else combination.add("null")
if(group3(i) exists)
combination.add(group3(i))
else combination.add("null")
print combination
</code></pre>