推荐网址链接

关于spfa优化和判环

https://blog.csdn.net/liangzhaoyang1/article/details/62423135

https://blog.csdn.net/crybymyself/article/details/53165306

https://blog.csdn.net/corncsd/article/details/18411437

树的重心、直径等

https://blog.csdn.net/DOLEAM/article/details/70943678

差分约束系统

https://blog.csdn.net/consciousman/article/details/53812818

http://www.cppblog.com/menjitianya/archive/2015/11/19/212292.html

倍增求lca

https://blog.csdn.net/lw277232240/article/details/72870644

例题：暗象石https://blog.csdn.net/qq_25978793/article/details/49362505

洛谷日报：https://www.luogu.org/discuss/show/48491

Tarjan算法详解：https://blog.csdn.net/qq_34374664/article/details/77488976

史上最全的Tarjan模板：https://blog.csdn.net/chai_jing/article/details/70147646

洛谷日报：骗分技巧https://www.luogu.org/blog/52913/special-program

快速幂详解：https://wenku.baidu.com/view/d65f294702768e9951e73883.html

神奇绘图网站：https://csacademy.com/app/graph_editor/

A*算法：https://www.cnblogs.com/21207-iHome/p/6048969.html