[费用流训练] - cool's Blog
[费用流训练]
cool
posted @ 2016年9月17日 17:05
in 图论
, 598 阅读
一直不会费用流,每天用单纯形骗分,被大骂一通,开始学习费用流。
费用流什么原理不是很清楚,但板子还是很好背的。
[方格取数]
矩阵每个元素最多取一次,从左上走到右下K次的权值最大值。
拆点,然后1条边是有费用的,流量1,其余边都是0费用,inf流量。
S向起点流K,终点向T流K。
[餐巾计划]
详见网络流24题。
拆点,i表示当天需要数,i'表示当天有多少没洗。
[bzoj3171循环格]
一个矩阵,每个格子连向一个相邻格,问至少改多少个连边,使从任意一个点出发都能回到该点。
最后一个条件即为,每个点出入度都为1。所以每个格子向原来连向的格子连0费用,1流量,其他连1费用,1流量即可。
[bzoj1070修车]
N个人修M辆车,求平均最小等待时间。
建图有点神,有点暴力的感觉。
2022年8月25日 18:38
Meghalaya Board Model Paper 2023 Class 8 Pdf Download with Answers for Bengali Medium, English Medium, Hindi Medium, Urdu Medium & Students for Small Answers, Long Answer, Very Long Answer Questions, and Essay Meghalaya Board Model Paper Class 8Type Questions to Term1 & Term2 Exams at official website. New Exam Scheme or Question Pattern for Sammittive Assignment Exams (SA1 & SA2): Very Long Answer (VLA), Long Answer (LA), Small Answer (SA), Very Small Answer (VSA), Single Answer, Multiple Choice and etc.
2025年2月24日 16:18
Thanks a lot for a fantastic blog post, exactly where will you come across all of your information? 代写
2025年2月25日 23:35
Locate which will article writing is not actually valued at the time period, you might recognise that discovering them free of charge is really a lot a great deal more an individual’s idea! Precisely why craft content articles together with throw away your time and energy when you are able become terrific content absolutely free! A lot of people discover utilizing just a dash of effort paid out diving the web page and looking at what’s going on they is able to leave and reveal a whole lot of function done with the particular means available. Learnician