增广路算法——Edmonds-Karp算法

增广路算法——Edmonds-Karp算法

以下是我的代码：

#include < stdio.h >
const   long  maxn = 107 ,INF = 2000007 ;
typedef  struct
{
     long  front,rear,count,item[maxn];
}queue;
void  clear(queue  & q)
{
    q.count = 0 ;
    q.front = 0 ;
    q.rear =- 1 ;
}
bool  empty(queue  & q)
{
     return  (q.count == 0 );
}
void  push(queue  & q, long  x)
{
    q.rear ++ ;
    q.item[q.rear] = x;
    q.count ++ ;
}
void  pop(queue  & q, long   & x)
{
    x = q.item[q.front];
    q.front ++ ;
    q.count -- ;
}
//   Queue

long  n,m,cap[maxn][maxn],flow[maxn][maxn];
long  s,t,fmax;

long  min( long  a, long  b)
{
     return  (a < b ? a:b);
}
void  read()
{
    scanf( " %ld%ld " , & n, & m);
    s = 1 ;t = n;
     for ( long  i = 1 ;i <= n;i ++ )
       for ( long  j = 1 ;j <= n;j ++ )
        cap[i][j] = 0 ;
     for ( long  i = 1 ;i <= m;i ++ )
    {
        long  a,b,w;
       scanf( " %ld%ld%ld " , & a, & b, & w);
       cap[a][b] = w;
    }
}
void  EK()
{
     long  tmp[maxn],father[maxn];
    queue q;clear(q);
     for ( long  i = 1 ;i <= n;i ++ )
       for ( long  j = 1 ;j <= n;j ++ )
        flow[i][j] = 0 ;
    fmax = 0 ;
     while ( true )
    {
        for ( long  i = 1 ;i <= n;i ++ ) tmp[i] = father[i] = 0 ;
       tmp[s] = INF;
       push(q,s);
        while ( ! empty(q))
       {
           long  i;
          pop(q,i);
           for ( long  j = 1 ;j <= n;j ++ )
             if ( ! tmp[j] && cap[i][j] > flow[i][j])
            {
               tmp[j] = min(tmp[i],cap[i][j] - flow[i][j]);
               father[j] = i;
               push(q,j);
            }
       }
        if (tmp[t] == 0 )  break ;
        for ( long  i = t;i != s;i = father[i])
       {
          flow[father[i]][i] += tmp[t];
          flow[i][father[i]] -= tmp[t];
       }
       fmax += tmp[t];
    }
    printf( " %ld\n " ,fmax);
}
int  main()
{
    freopen( " data.in " , " r " ,stdin);
    freopen( " data.out " , " w " ,stdout);
    read();
    EK();
return   0 ;
}