动态规划

入门总概：https://www.sohu.com/a/153858619_466939

                  https://blog.youkuaiyun.com/feizaosyuacm/article/details/53846323

                  http://www.360doc.com/content/16/0906/13/30724179_588796517.shtml

三种背包问题：https://blog.youkuaiyun.com/tinyguyyy/article/details/51203935

区间DP：https://blog.youkuaiyun.com/Ginsn/article/details/81563082

                平行四边形优化：https://blog.youkuaiyun.com/noiau/article/details/72514812

                                             https://www.cnblogs.com/zxndgv/archive/2011/08/02/2125242.html

线性DP：https://www.cnblogs.com/rhythmic/p/5398953.html