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Re:dp的详细说明

Posted by qiqilrq at 2007-10-24 15:44:44 on Problem 3046
In Reply To:哦？还是没明白，我比较愚笨，希望能再说清楚些啊，谢谢了。。 Posted by:richardxx at 2007-10-23 22:24:52 
设一维数组Cb[]记录了集合S={n1·a, n2·b}的组合数，即Cb[i]记录S的i-组合数。
那么集合S`={n1·a, n2·b, n3·c}的k-组合数为：
Cb[k-n3]+Cb[k-n3+1]+…+Cb[k]
其中，Cb[i]=0 if i<0 or i>n1+n2

可以应用到任何集合S`=S+n·c的情况
然后循环地累加加上去就行了
实际上我也是看到discuss的问题代码才知道的...
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