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对于此题使用贪心算法的分析(希望大牛补充哦)

Posted by lqc at 2010-04-09 10:19:28 on Problem 1083 and last updated at 2010-04-09 11:36:52
将s从大到小排序或将t从小到大排序进行贪心是不能得到全局最优的,它只能保证是当前剩余房间的局部最优,看看这组数据便知:
1
4
2 4
1 6
10 12
5 14
答案为20
(数据来自dicuss)

将s从小到大排序进行贪心则可以得到全局最优,但不能保证局部最优(局部最优是指选取最多的桌子进行移动)。
另外,注意看题目中给出的图,1-2,3-4,5-6...是占用走廊的相同空间,所以2-3 4-5的最优时间为20。

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