首先看一个题：https://leetcode-cn.com/problems/burst-balloons/
这个题目可以使用分治法来做。
参考：
- https://leetcode-cn.com/problems/burst-balloons/solution/dui-fen-zhi-fa-ti-jie-de-jie-du-by-chuck-bass/
- https://leetcode-cn.com/problems/burst-balloons/solution/chao-xiang-xi-hui-su-dao-fen-zhi-dao-dp-by-niu-you/
- https://leetcode-cn.com/problems/burst-balloons/solution/cyu-yan-ti-jie-qian-xi-qu-jian-dpyu-fen-zhi-fa-by-/