求牛人解决概率问题啊,英文题目木有看懂. 在概率论中defective和 antennas 是什么意思啊?!
问题描述：
求牛人解决概率问题啊,英文题目木有看懂. 在概率论中defective和 antennas 是什么意思啊?!
Consider a set of n antennas of which m are defective and n-m are functional and assume that all of the defectives and all of the functionals are considered indistinguishable. How many linear orderings are there in which no two defectives are consecutive?
求指教啊！！！！！！
答
n个天线,m个坏的,n-m个好的,问有多少种排列使得没有坏的是连一起的
问题可以转化为
在n-m个当中插板有多少种插法
一共有n-m+1个地方可以插板
选出m个地方插坏的
所以答案是
n-m+1 find m