poj2195&&hdu1533 最小费用流

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<queue>
#include<stdlib.h>
#define INF 1000000000
using namespace std;
const int maxn = 1100;
struct Set
{
int x,y;
}mnum[110*110],hnum[110*110];
struct node
{
int to;
int v;
int flag;
int cost;
int next;
}edge[maxn*maxn/2];
char map[110][110];
int n,m,cou1,cou2,index,head[maxn],s,t,pre[maxn],fpre[maxn],N,dis[maxn];
int Get(int i,int j)
{
return abs(mnum[i].x-hnum[j].x)+abs(mnum[i].y-hnum[j].y);
}
void add(int x,int y,int v,int cost)
{
edge[index].to=y;
edge[index].v=v;
edge[index].cost=cost;
edge[index].flag=index+1;
edge[index].next=head[x];
head[x]=index++;
edge[index].to=x;
edge[index].v=0;
edge[index].cost=-cost;
edge[index].flag=index-1;
edge[index].next=head[y];
head[y]=index++;
}
void makemap()
{
int i,j;
cou1=cou2=0;
for(i=0;i<n;i++)
{
for(j=0;j<m;j++)
{
if(map[i][j]=='m')
{
mnum[++cou1].x=i;
mnum[cou1].y=j;
}
else if(map[i][j]=='H')
{
hnum[++cou2].x=i;
hnum[cou2].y=j;
}
}
}
index=1;
memset(head,-1,sizeof(head));
N=cou1+cou2+1;
s=0;
t=cou1+cou2+1;
for(i=1;i<=cou1;i++)
add(s,i,1,0);
for(i=1;i<=cou2;i++)
add(i+cou1,t,1,0);
for(i=1;i<=cou1;i++)
{
for(j=1;j<=cou2;j++)
{
add(i,j+cou1,1,Get(i,j));
}
}
}
bool spfa(int s,int t)
{
int vis[maxn];
queue<int>q;
memset(pre,-1,sizeof(pre));
memset(vis,0,sizeof(vis));
int i;
for(i=0;i<=N;i++)
dis[i]=INF;
vis[s]=1;
dis[s]=0;
pre[s]=0;
q.push(s);
while(!q.empty())
{
int u=q.front();
q.pop();
vis[u]=0;
for(i=head[u];i!=-1;i=edge[i].next)
{
if(edge[i].v&&dis[edge[i].to]>dis[u]+edge[i].cost)
{
dis[edge[i].to]=dis[u]+edge[i].cost;
if(!vis[edge[i].to])
{
vis[edge[i].to]=1;
q.push(edge[i].to);
}
pre[edge[i].to]=u;
fpre[edge[i].to]=i;
}
}
}
if(dis[t]>=INF)return false;
return true;
}
int main()
{
int i,j;
while(~scanf("%d%d",&n,&m))
{
if(!n&&!m)break;
for(i=0;i<n;i++)
scanf("%s",map[i]);
makemap();
int ans=0;
while(spfa(s,t))
{
int minflow=INF;
for(i=t;i!=0;i=pre[i])
{
if(minflow>edge[fpre[i]].v)
minflow=edge[fpre[i]].v;
}
ans+=minflow*dis[t];
for(i=t;i!=0;i=pre[i])
{
edge[fpre[i]].v-=minflow;
edge[edge[fpre[i]].flag].v+=minflow;
}
}
printf("%d\n",ans);
}
}

#include<stdio.h>
#include<string.h>
#include<algorithm>
#define INF 99999999
#define maxn 105
using namespace std;
struct node
{
int x;
int y;
}h[maxn],m[maxn];
char g[maxn][maxn];
int map[maxn][maxn],pr[maxn],pl[maxn],visr[maxn],visl[maxn],match[maxn],slack[maxn];
int col,row;
void init(int x)
{
int i,j;
for(i=0;i<=x;i++)
for(j=0;j<=x;j++)
if(i==j)map[i][j]=0;
else map[i][j]=INF;
}
int dfs(int u,int n)
{
int i,j;
visl[u]=1;
for(i=0;i<n;i++)
{
if(!visr[i])
{
int val=pl[u]+pr[i]-map[u][i];
if(val==0)
{
visr[i]=1;
if(match[i]==-1||dfs(match[i],n))
{
match[i]=u;
return 1;
}
}
if(val>0&&val<slack[i])
slack[i]=val;
}
}
return 0;
}
int km(int n)
{
int i,j;
memset(pr,0,sizeof(pr));
memset(match,-1,sizeof(match));
for(i=0;i<n;i++)
pl[i]=INF;
for(i=0;i<n;i++)
{
for(j=0;j<n;j++)
slack[j]=INF;
while(1)
{
memset(visr,0,sizeof(visr));
memset(visl,0,sizeof(visl));
if(dfs(i,n))break;
int k=INF;
for(j=0;j<n;j++)
{
if(!visr[j]&&slack[j]<k)
k=slack[j];
}
for(j=0;j<n;j++)
{
if(visl[j])
pl[j]-=k;
if(visr[j])
pr[j]+=k;
}
}
}
int res=0;
for(i=0;i<n;i++)
{
res+=map[match[i]][i];
}
return res;
}
int main()
{
int i,j;
while(scanf("%d%d",&row,&col)!=EOF)
{
if(row==0&&col==0)
break;
int count1=0,count2=0;
for(i=0;i<row;i++)
scanf("%s",g[i]);
for(i=0;i<row;i++)
for(j=0;j<col;j++)
{
if(g[i][j]=='H')
{
h[count1].x=i;h[count1++].y=j;
}
else if(g[i][j]=='m')
{
m[count2].x=i;m[count2++].y=j;
}
}
init(count1);
for(i=0;i<count1;i++)
for(j=0;j<count2;j++)
{
map[i][j]=-(abs(h[i].x-m[j].x)+abs(h[i].y-m[j].y));
}
printf("%d\n",-km(count1));
}
}