HDU 3081 Marriage Match II【并查集+二分图最大匹配】

  1 #include <iostream>
  2 #include <cstdio>
  3 #include <cstring>
  4 #include <vector>
  5 using namespace std;
  6 
  7 const int maxn = 105;
  8 const int INF = 1000000000;
  9 
 10 int fa[maxn];
 11 void init(int x) {
 12     for(int i = 0; i <= x; i++) {
 13         fa[i] = i;
 14     }
 15 }
 16 
 17 int find(int u) {
 18     if(fa[u] == u) return u;
 19     return fa[u] = find(fa[u]);
 20 }
 21 
 22 void unin(int u, int v) {
 23     int fu = find(u);
 24     int fv = find(v);
 25     if(fu != fv) {
 26         fa[fu] = fv;
 27     }
 28 }
 29 
 30 
 31 int Link[maxn];
 32 int W[maxn][maxn];
 33 int vis[maxn];
 34 int n;
 35 
 36 int Find(int i) {
 37     for(int j = 1; j <= n; j++) {
 38         if(W[i][j] && !vis[j]) {
 39             vis[j] = 1;
 40             if(Link[j] == -1 || Find(Link[j]) ) {
 41                 Link[j] = i;
 42                 return true;
 43             }
 44         }
 45     }
 46     return false;
 47 }
 48 
 49 bool Match() {
 50     memset(Link, -1, sizeof(Link));
 51     for(int i = 1; i <= n; i++) {
 52         memset(vis, 0, sizeof(vis));
 53         if(!Find(i)) return false;
 54     }
 55     return true;
 56 }
 57 
 58 int Solve() {
 59     int cnt = 0;
 60     while(1) {
 61         if(Match() ) {
 62             cnt ++;
 63             for(int j = 1; j <= n; j++) {
 64                 W[Link[j]][j] = 0;
 65             }
 66         } else break;
 67     }
 68     return cnt;
 69 }
 70 
 71 vector<int> v[maxn * maxn];
 72 
 73 int main() {
 74     int m, f;
 75     int a, b;
 76     int c, d;
 77     int t;
 78     scanf("%d", &t);
 79     while(t--) {
 80         scanf("%d %d %d", &n, &m, &f);
 81         memset(W, 0, sizeof(W));
 82         init(n);
 83         for(int i = 0; i <= n; i++) v[i].clear();
 84         for(int i = 1; i <= m; i++) {
 85             scanf("%d %d", &a, &b);
 86             v[a].push_back(b);
 87         }
 88         for(int i = 1; i <= f; i++) {
 89             scanf("%d %d",&c, &d);
 90             unin(c, d);
 91         }
 92         for(int i = 1; i <= n; i++) {
 93             for(int j = 1; j <= n; j++) {
 94                 if(find(i) == find(j) ) {
 95                     for(int k = 0; k < v[j].size(); k++) {
 96                         W[i][v[j][k]] = 1;
 97                     }
 98                 }
 99             }
100         }
101         printf("%d\n", Solve() ) ;
102     }
103     return 0;
104 }