Uva-12264-Risk

#include<cstdio>
#include<cstring>
#include<iostream>
#include<queue>
using namespace std;
const int inf=1<<29;
const int maxn=210;
const int maxm=maxn*maxn;
int st,des,e,n,head[maxn],pnt[maxm],nxt[maxm],flow[maxm],level[maxn];
int a[maxn];
char map[maxn][maxn];
queue<int> q;
void AddEdge(int u,int v,int f)
{
pnt[e]=v;nxt[e]=head[u];flow[e]=f;head[u]=e++;
pnt[e]=u;nxt[e]=head[v];flow[e]=0;head[v]=e++;
}
int Build(int val)
{
int sum=0;
memset(head,-1,sizeof(head));
e=st=0;des=2*n+1;
for(int i=1;i<=n;i++)
{
bool isborder=false;
if(!a[i])
continue;
AddEdge(st,i,a[i]);
AddEdge(i,i+n,a[i]);
for(int j=1;j<=n;j++)
{
if(map[i][j]=='Y')
{
if(!a[j])
isborder=true;
else
AddEdge(n+i,j,inf);
//printf("Add %d %d\n",i,j);
}
}
if(isborder)
{
AddEdge(i,des,val);
//printf("ADDDB %d %d\n",i,des);
sum+=val;
}
else
{
//printf("AdddA %d %d\n",i,des);
AddEdge(i,des,1);
sum+=1;
}
}
return sum;
}
bool BFS()
{
memset(level,0,sizeof(level));
level[st]=1;
q.push(st);
while(!q.empty())
{
int u=q.front();
q.pop();
for(int i=head[u];i!=-1;i=nxt[i])
if(flow[i]&&!level[pnt[i]])
{
level[pnt[i]]=level[u]+1;
q.push(pnt[i]);
}
}
return level[des];
}
int DFS(int u,int maxf)
{
if(u==des||!maxf)
return maxf;
for(int i=head[u],t;i!=-1;i=nxt[i])
if(level[pnt[i]]==level[u]+1&&(t=DFS(pnt[i],min(flow[i],maxf))))
{
flow[i]-=t;
flow[i^1]+=t;
return t;
}
return level[u]=0;
}
int maxflow()
{
int ans=0;
while(BFS())
while(1)
{
int val=DFS(st,inf);
if(!val)
break;
ans+=val;
}
return ans;
}
int main()
{
int T;
scanf("%d",&T);
while(T--)
{
scanf("%d",&n);
for(int i=1;i<=n;i++)
scanf("%d",&a[i]);
for(int i=1;i<=n;i++)
scanf("%s",map[i]+1);
int sl=0,sr=100010,ans=0;
while(sl<=sr)
{
// printf("LRRRR %d %d\n",sl,sr);
int mid=(sl+sr)>>1;
int val=Build(mid);
int f=maxflow();
//  printf("FFFF %d %d %d\n",val,f,mid);
if(f==val)
{
sl=mid+1;
ans=mid;
}
else
sr=mid-1;
}
printf("%d\n",ans);
}
return 0;
}