今天复习二分匹配,A 了一道模板题. 二分匹配需要理解增广路的寻找.用dfs来更新最大匹配.注意一些点:赋初值:愚蠢地把==写成了= ; 然后match的记值;每个点都要重新走一遍. #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define INF 80005 #define maxn 405 using namespace std; int n,m,a…

poj1274 题意: 有n个奶牛, m个畜舍, 每个畜舍最多装1头牛,每只奶牛只有在自己喜欢的畜舍里才能产奶. 求最大产奶量. 分析: 其实题意很明显, 二分图的最大匹配, 匈牙利算法. #include<iostream> #include<cstdio> #include<string.h> #include<cstring> using namespace std; ], ans[], map1[][]; int dfs(int x)//如果有增广路…

题目链接: https://vjudge.net/problem/POJ-1274 题目大意: 有n个奶牛和m个谷仓,现在每个奶牛有自己喜欢去的谷仓,并且它们只会去自己喜欢的谷仓吃东西,问最多有多少奶牛能够吃到东西 输入第一行给出n与m接着n行每行第一个数代表这个奶牛喜欢的谷仓的个数P,后面接着P个数代表这个奶牛喜欢哪个谷仓 思路: 二分图模板 #include<iostream> #include<vector> #include<cstring> #include&…

The Perfect Stall Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 23911   Accepted: 10640 Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering p…

The Perfect Stall Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 22809   Accepted: 10161 Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering p…

Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering problems, all the stalls in the new barn are different. For the first week, Farmer John randomly assigne…

http://poj.org/problem?id=1274 (题目链接) 题意 懒得写了 Solution 二分图匹配裸题.注意清空数组. 代码 // poj3020 #include<algorithm> #include<iostream> #include<cstdlib> #include<cstring> #include<cstdio> #include<cmath> #define LL long long #defi…

主题链接: id=1274">http://poj.org/problem? id=1274 题目大意: 有N头奶牛(编号1~N)和M个牛棚(编号1~M). 每头牛仅仅可产一次奶.每一个牛棚也仅仅同意一仅仅牛产奶. 如今给出每头奶牛喜欢去的牛棚的编号.问:最多有多少头奶牛能完毕产奶. 思路: 二分图最大匹配问题,建立一个图,用行来表示奶牛,用列来表示牛棚.将奶牛和喜欢去的牛棚编号 连边. 然后用匈牙利算法DFS版或BFS版求二分图的最大匹配数就可以.这里用了匈牙利算法DFS版. AC代码:…

The Perfect Stall Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 25739   Accepted: 11444 Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering p…

The Perfect Stall Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 23911   Accepted: 10640 Description Farmer John completed his new barn just last week, complete with all the latest milking technology. Unfortunately, due to engineering p…