1 //KM 邻接矩阵
2 const int INF = 0x3f3f3f3f;
3
4 int n, pay[305][305];
5 int match[305];//y方点对应的x方点
6 int lx[305], ly[305];//标号
7 int slack[305];//记录标号改变量
8 bool visx[305], visy[305];
9
10 bool Hungary( int s ){
11 visx[s] = true;
12
13 for( int i = 1; i <= n; i++ ){
14 if( visy[i] ) continue;
15 if( lx[s] + ly[i] == pay[s][i] ){
16 visy[i] = true;
17 if( match[i] == -1 || Hungary( match[i] ) ){
18 match[i] = s;
19 return true;
20 }
21 }
22 else slack[i] = min( slack[i], lx[s] + ly[i] - pay[s][i] );
23 }
24
25 return false;
26 }
27
28 void KM(){
29 memset( match, -1, sizeof( match ) );
30 memset( lx, 0, sizeof( lx ) );
31 memset( ly, 0, sizeof( ly ) );
32 for( int i = 1; i <= n; i++ )
33 for( int j = 1; j <= n; j++ )
34 lx[i] = max( lx[i], pay[i][j] );
35
36 for( int i = 1; i <= n; i++ ){
37 memset( slack, INF, sizeof( slack ) );
38 while( 1 ){
39 memset( visx, false, sizeof( visx ) );
40 memset( visy, false, sizeof( visy ) );
41
42 if( Hungary( i ) ) break;
43 else{
44 int temp = INF;
45 for( int i = 1; i <= n; i++ )
46 if( !visy[i] )
47 temp = min( temp, slack[i] );
48 for( int i = 1; i <= n; i++ ){
49 if( visx[i] )
50 lx[i] -= temp;
51 if( visy[i] )
52 ly[i] += temp;
53 else
54 slack[i] -= temp;
55 }
56 }
57 }
58 }
59 }
1 //前向星 + 匈牙利bfs
2 const int MAXN = 105;
3 const int MAXM = 10005;
4 ////////////////////////////////////
5 struct Match{
6 int to, next;
7 }ptos[MAXM], stop[MAXM];
8 int pcnt, ph[MAXN], scnt, sh[MAXN];
9
10 int pmatch[MAXN], smatch[MAXN];//p和s匹配的对象
11 int flag[MAXN], pre[MAXN];
12
13 inline void init(){
14 memset( pmatch, -1, sizeof( pmatch ) );
15 memset( smatch, -1, sizeof( smatch ) );
16 memset( ph, -1, sizeof( ph ) );
17 memset( sh, -1, sizeof( sh ) );
18 memset( flag, -1, sizeof( flag ) );
19 pcnt = scnt = 0;
20 }
21
22 void match_add( int from, int to ){
23 ptos[pcnt].to = to;
24 ptos[pcnt].next = ph[from];
25 ph[from] = pcnt++;
26
27 swap( from, to );
28
29 stop[scnt].to = to;
30 stop[scnt].next = sh[from];
31 sh[from] = scnt++;
32 }
33
34 int maxmatch(){
35 int ans = 0;
36
37 for( int i = 1; i <= n; i++ ){
38 if( pmatch[i] == -1 ){
39 queue<int> Q;
40 Q.push( i );
41 pre[i] = -1;
42 bool ok = false;
43
44 while( !Q.empty() && !ok ){
45 int pos = Q.front(); Q.pop();
46
47 for( int k = ph[pos]; k != -1 && !ok; k = ptos[k].next ){
48 int v = ptos[k].to;
49 if( flag[v] != i ){
50 flag[v] = i;
51 Q.push( smatch[v] );
52 if( smatch[v] == -1 ){
53 ok = true;
54 int tempp = pos, temps = v;
55 while( tempp != -1 ){
56 int x = pmatch[tempp];
57 pmatch[tempp] = temps;
58 smatch[temps] = tempp;
59 tempp = pre[tempp];
60 temps = x;
61 }
62 }
63 else pre[smatch[v]] = pos;
64 }
65 }
66 }
67 if( pmatch[i] != -1) ans++;
68 }
69 }
70
71 return ans;
72 }
