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排列组合的题

Posted by majia5 at 2009-08-05 23:41:51 on Problem 3421
后面的每一个数都是选择了一个X的素因子乘上去,才能保证序列最长,于是长度m就是X的素因子的总数
如12=2^2 * 3,素因子总数为3

下面来看有几种这个长度方案,可以知道我们把每一个素因子拿去放,表示第i到第i+1项是乘了某个素因子,假设素因子的个数分别为P[0],P[1]...P[k]
然后c(m,p[0]) * c(m-p[0],p[1]) * .... * c(m-p[0]-p[1]-...-p[k-1],p[k])


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