UVA - 753 A Plug for UNIX——二分图最大基数匹配

用了ek最大流+flody闭包，然后瞎写一通

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <map>
using namespace std;
const int INF = 0x3f3f3f3f;
const int maxn = 1e5;
struct Data {
    string s;
    int link, id;
}data1[110], data2[110];
map<string, int> ma;
int G[1000][1000];

struct Edge {
    int from, to, cap, flow;
    Edge(int u, int v, int c, int f) : from(u), to(v), cap(c), flow(f) {}
};

struct EdmondsKarp {
    int n, m;
    vector<Edge> edges;
    vector<int> G[maxn];
    int p[maxn], a[maxn];

    void init(int x) {
        n = x;
        edges.clear();
        for (int i = 0; i < n; i++) G[i].clear();
    }

    void addedge(int from, int to, int cap) {
        edges.push_back(Edge(from, to, cap, 0));
        edges.push_back(Edge(to, from, 0, 0));
        m = edges.size();
        G[from].push_back(m - 2);
        G[to].push_back(m - 1);
    }

    int maxflow(int s, int t) {
        int flow = 0;
        while (true) {
            memset(a, 0, sizeof(a));
            queue<int> q;
            p[s] = 0, a[s] = INF;
            q.push(s);
            while (!q.empty()) {
                int u = q.front(); q.pop();
                for (int i = 0; i < G[u].size(); i++) {
                    Edge &e = edges[G[u][i]];
                    if (!a[e.to] && e.cap > e.flow) {
                        p[e.to] = G[u][i];
                        a[e.to] = min(a[u], e.cap - e.flow);
                        q.push(e.to);
                    }
                }
                if (a[t]) break;
            }
            if (!a[t]) break;
            for (int u = t; u != s; u = edges[p[u]].from) {
                edges[p[u]].flow += a[t];
                edges[p[u]^1].flow -= a[t];
            }
            flow += a[t];
        }
        return flow;
    }
}ek;

int main() {
    int T, flag = 0; scanf("%d", &T);
    while (T--) {
        ma.clear();
        memset(G, 0, sizeof(G));
        int cnt = 0;
        int n; scanf("%d", &n);
        for (int i = 0; i < n; i++) {
            cin >> data1[i].s;
            if (!ma[data1[i].s]) ma[data1[i].s] = ++cnt;
            data1[i].id = ma[data1[i].s];
        }
        int m; scanf("%d", &m);
        for (int i = 0; i < m; i++) {
            string s; cin >> data2[i].s >> s;
            if (!ma[s]) ma[s] = ++cnt;
            if (!ma[data2[i].s]) ma[data2[i].s] = ++cnt;
            int id1 = ma[s], id2 = ma[data2[i].s];
            data2[i].link = id1, data2[i].id = id2;
        }
        int k; scanf("%d", &k);
        for (int i = 0; i < k; i++) {
            string s1, s2; cin >> s1 >> s2;
            if (!ma[s1]) ma[s1] = ++cnt;
            if (!ma[s2]) ma[s2] = ++cnt;
            int id1 = ma[s1], id2 = ma[s2];
            G[id1][id2] = 1;
        }
        for (int t = 0; t <= cnt; t++) {
            for (int i = 0; i <= cnt; i++) {
                for (int j = 0; j <= cnt; j++) {
                    G[i][j] = G[i][j] || (G[i][t] && G[t][j]);
                }
            }
        }
        int s = ++cnt;
        int t = ++cnt;
        ek.init(cnt + 10);
        for (int i = 0; i < n; i++) ek.addedge(s, data1[i].id, 1);
        for (int i = 0; i < m; i++) ek.addedge(data2[i].id, t, 1);
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                int id = data1[i].id;
                if (data2[j].link == id || G[data2[j].link][id] || G[id][data2[j].link]) ek.addedge(id, data2[j].id, INF);
            }
        }
        if (flag++) printf("\n");
        printf("%d\n", m - ek.maxflow(s, t));
    }
}