[HDOJ1281]棋盘游戏（二分图最大匹配）

  1 /*
  2 ━━━━━┒ギリギリ♂ eye！
  3 ┓┏┓┏┓┃キリキリ♂ mind！
  4 ┛┗┛┗┛┃＼○／
  5 ┓┏┓┏┓┃ /
  6 ┛┗┛┗┛┃ノ)
  7 ┓┏┓┏┓┃
  8 ┛┗┛┗┛┃
  9 ┓┏┓┏┓┃
 10 ┛┗┛┗┛┃
 11 ┓┏┓┏┓┃
 12 ┛┗┛┗┛┃
 13 ┓┏┓┏┓┃
 14 ┃┃┃┃┃┃
 15 ┻┻┻┻┻┻
 16 */
 17 #include <algorithm>
 18 #include <iostream>
 19 #include <iomanip>
 20 #include <cstring>
 21 #include <climits>
 22 #include <complex>
 23 #include <fstream>
 24 #include <cassert>
 25 #include <cstdio>
 26 #include <bitset>
 27 #include <vector>
 28 #include <deque>
 29 #include <queue>
 30 #include <stack>
 31 #include <ctime>
 32 #include <set>
 33 #include <map>
 34 #include <cmath>
 35 using namespace std;
 36 #define fr first
 37 #define sc second
 38 #define cl clear
 39 #define BUG puts("here!!!")
 40 #define W(a) while(a--)
 41 #define pb(a) push_back(a)
 42 #define Rint(a) scanf("%d", &a)
 43 #define Rll(a) scanf("%I64d", &a)
 44 #define Rs(a) scanf("%s", a)
 45 #define Cin(a) cin >> a
 46 #define FRead() freopen("in", "r", stdin)
 47 #define FWrite() freopen("out", "w", stdout)
 48 #define Rep(i, len) for(int i = 0; i < (len); i++)
 49 #define For(i, a, len) for(int i = (a); i < (len); i++)
 50 #define Cls(a) memset((a), 0, sizeof(a))
 51 #define Clr(a, x) memset((a), (x), sizeof(a))
 52 #define Full(a) memset((a), 0x7f7f7f, sizeof(a))
 53 #define lrt rt << 1
 54 #define rrt rt << 1 | 1
 55 #define pi 3.14159265359
 56 #define RT return
 57 #define lowbit(x) x & (-x)
 58 #define onecnt(x) __builtin_popcount(x)
 59 typedef long long LL;
 60 typedef long double LD;
 61 typedef unsigned long long ULL;
 62 typedef pair<int, int> pii;
 63 typedef pair<string, int> psi;
 64 typedef pair<LL, LL> pll;
 65 typedef map<string, int> msi;
 66 typedef vector<int> vi;
 67 typedef vector<LL> vl;
 68 typedef vector<vl> vvl;
 69 typedef vector<bool> vb;
 70 
 71 const int maxn = 310;
 72 int nu, nv;
 73 int G[maxn][maxn];
 74 int linker[maxn];
 75 bool vis[maxn];
 76 
 77 bool dfs(int u) {
 78     For(v, 1, nv+1) {
 79         if(G[u][v] && !vis[v]) {
 80             vis[v] = 1;
 81             if(linker[v] == -1 || dfs(linker[v])) {
 82                 linker[v] = u;
 83                 return 1;
 84             }
 85         }
 86     }
 87     return 0;
 88 }
 89 
 90 int hungary() {
 91     int ret = 0;
 92     Clr(linker, -1);
 93     For(u, 1, nu+1) {
 94         Cls(vis);
 95         if(dfs(u)) ret++;
 96     }
 97     return ret;
 98 }
 99 
100 int n, m, k;
101 int mp[maxn][maxn];
102 
103 int main() {
104     // FRead();
105     int u, v, _ = 1;
106     while(~scanf("%d%d%d",&n,&m,&k)) {
107         Cls(mp); Cls(G);
108         nu = n; nv = m;
109         W(k) {
110             Rint(u); Rint(v);
111             G[u][v] = 1;
112         }
113         int ret = hungary();
114         int ans = 0;
115         For(i, 1, nu+1) {
116             For(j, 1, nv+1) {
117                 if(G[i][j]) {
118                     G[i][j] = 0;
119                     if(ret != hungary()) ans++;
120                     G[i][j] = 1;
121                 }
122             }
123         }
124         printf("Board %d have %d important blanks for %d chessmen.\n", _++, ans, ret);
125     }
126     RT 0;
127 }