OJ-Problems-Source/HDOJ/1533_autoAC.cpp
2016-08-14 17:42:04 +08:00

131 lines
2.9 KiB
C++

#include<stdio.h>
#include<queue>
#include<iostream>
#define INF 1000000000
#define N 1005
using namespace std;
int list[N],dis[N],hx[N],hy[N],px[N],py[N],tot,pre[N],pr[N];
char map[205][205];
struct dian
{
int date,value,next,cost;
}cun[2000005];
void add(int a,int b,int c,int d)
{
cun[++tot].date=b;
cun[tot].value=c;
cun[tot].next=list[a];
cun[tot].cost=d;
list[a]=tot;
cun[++tot].date=a;
cun[tot].value=0;
cun[tot].next=list[b];
cun[tot].cost=-d;
list[b]=tot;
}
int abss(int a)
{
if(a>0) return a;
return -a;
}
int spfa(int s,int t)
{
queue<int> p;
int vis[N];
for(int i=0;i<1005;i++)
{
dis[i]=INF;
vis[i]=0;
pre[i]=-1;
}
dis[s]=0;
p.push(s);
int k;
while(!p.empty())
{
k=p.front();
p.pop();
vis[k]=0;
for(int i=list[k];i;i=cun[i].next)
{
int w=cun[i].value;
int c=cun[i].cost;
int to=cun[i].date;
if(w>0&&dis[to]>dis[k]+c)
{
dis[to]=dis[k]+c;
pre[to]=k;
pr[to]=i;
if(!vis[to])
{
vis[to]=1;
p.push(to);
}
}
}
}
if(dis[t]>=INF) return 0;
return 1;
}
int maxflow(int s,int t)
{
int min=INF;
int sum=0;
while(spfa(s,t))
{
for(int i=t;i!=s;i=pre[i])
{
if(min<cun[pr[i]].value)
min=cun[pr[i]].value;
}
for(int i=t;i!=s;i=pre[i])
{
cun[pr[i]].value-=min;
cun[pr[i]^1].value+=min;
}
sum+=dis[t];
}
return sum;
}
void clear()
{
memset(list,0,sizeof(list));
tot=1;
}
int main()
{
int n,m;
while(scanf("%d%d",&n,&m)!=EOF)
{
if(n==0&&m==0) break;
getchar();
clear();
int count,kk;
count=kk=1;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=m;j++)
{
scanf("%c",&map[i][j]);
if(map[i][j]=='H') {hx[count]=i; hy[count++]=j;}
if(map[i][j]=='m') {px[kk]=i; py[kk++]=j;}
}
getchar();
}
for(int i=1;i<kk;i++)
{
add(1,i+1,1,0);
for(int j=1;j<count;j++)
{
int w=abss(hx[i]-px[j])+abs(hy[i]-py[j]);
add(i+1,count+1+j,1,w);
}
}
for(int i=1;i<count;i++)
{
add(count+1+i,2*count+10,1,0);
}
printf("%d\n",maxflow(1,2*count+10));
}
}