最小费用最大流 参考文献: 理论 http://blog.youkuaiyun.com/smartxxyx/article/details/9293665 代码实现 http://blog.youkuaiyun.com/fobdddf/article/details/19615651 题目原型 http://www.myexception.cn/program/1725711.html SPFA算法学习: http://www.cnblogs.com/shadowland/p/5870640.html