hdu--3488--km<先人太聪明了>

  1 #include <iostream>
  2 #include <cstring>
  3 #include <algorithm>
  4 using namespace std;
  5 
  6 int n;
  7 const int size = 220;
  8 const int inf = 0x3f3f3f3f;
  9 int mp[size][size];
 10 int lx[size] , ly[size];
 11 int linker[size];
 12 bool visx[size] , visy[size];
 13 int slack[size];
 14 
 15 bool dfs( int x )
 16 {
 17     int temp;
 18     visx[x] = true;
 19     for( int y = 1 ; y<=n ; y++ )
 20     {
 21         if( !visy[y] )
 22         {
 23             temp = lx[x] + ly[y] - mp[x][y];
 24             if( temp==0 )
 25             {
 26                 visy[y] = true;
 27                 if( linker[y] == -1||dfs(linker[y]) )
 28                 {
 29                     linker[y] = x;
 30                     return true;
 31                 }    
 32             }
 33             else if( slack[y] > temp )
 34             {
 35                 slack[y] = temp;    
 36             }
 37         }
 38     }
 39     return false;
 40 }
 41 
 42 void km( )
 43 {
 44     int temp , ans = 0;
 45     memset( ly , 0 , sizeof(ly) );//开始Y集合中顶标初始化为0
 46     memset( linker , -1 , sizeof(linker) );//Y集合中某元素的边的另一端点
 47     for( int i = 1 ; i<=n ; i++ )
 48     {
 49         lx[i] = -inf;
 50         for( int j = 1 ; j<=n ; j++ )
 51         {
 52             if( mp[i][j]>lx[i] )
 53             {
 54                 lx[i] = mp[i][j];
 55             }
 56         }
 57     }
 58     for( int x = 1 ; x<=n ; x++ )
 59     {
 60         for( int i = 1 ; i<=n ; i++ )
 61         {
 62             slack[i] = inf;
 63         }
 64         while( true )
 65         {
 66             memset( visx , false , sizeof(visx) );
 67             memset( visy , false , sizeof(visy) );
 68             if( dfs(x) )
 69                 break;
 70             temp = inf;
 71             for( int y = 1 ; y<=n ; y++ )
 72             {
 73                 if( !visy[y] && temp>slack[y] )
 74                     temp = slack[y];
 75             }
 76             for( int x = 1 ; x<=n ; x++ )
 77             {
 78                 if( visx[x] )
 79                     lx[x] -= temp;
 80             }
 81             for( int y = 1 ; y<=n ; y++ )
 82             {
 83                 if( visy[y] )
 84                     ly[y] += temp;
 85                 else
 86                     slack[y] -= temp;
 87             }
 88         }
 89     }
 90     for( int i = 1 ; i<=n ; i++ )
 91     {
 92         ans += mp[ linker[i] ][i];
 93         cout << linker[i] << " " << i << endl;
 94     }
 95     cout << -ans << endl;
 96 }
 97 
 98 int main()
 99 {
100     int t , m , st , end , dist;
101     while( cin>>t )
102     {
103         while( t-- )
104         {
105             memset( mp , -inf , sizeof(mp) );
106             cin >> n >> m;
107             while( m-- )
108             {
109                 cin >> st >> end >> dist;
110                 mp[st][end] = mp[st][end] < -dist ? -dist : mp[st][end];
111             }
112             km();
113         }
114     }    
115     return 0;
116 }