You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
73 lines
1.7 KiB
C++
73 lines
1.7 KiB
C++
#include <cstdio>
|
|
#include <cstring>
|
|
#include <algorithm>
|
|
using namespace std;
|
|
typedef unsigned long long ull;
|
|
const int N=1005,M=20050;
|
|
ull v[N];
|
|
inline ull getHash(char*s)
|
|
{
|
|
ull ret=0;
|
|
for(; *s; s++)
|
|
ret=ret*131+*s;
|
|
return ret;
|
|
}
|
|
int adj[N],nxt[M],to[M],ecnt;
|
|
inline void addEdge(int f,int t)
|
|
{
|
|
ecnt++;
|
|
nxt[ecnt]=adj[f];
|
|
to[ecnt]=t;
|
|
adj[f]=ecnt;
|
|
}
|
|
int dis[N];
|
|
void spfa(int s)
|
|
{
|
|
static int que[N<<2];
|
|
static bool inq[N];
|
|
memset(inq,0,sizeof(inq));
|
|
memset(dis,0x3f3f3f3f,sizeof(dis));
|
|
int h,t;
|
|
for(h=t=0,dis[s]=0,que[t++]=s; h^t; inq[h++]=false)
|
|
for(int e=adj[que[h]]; e; e=nxt[e])
|
|
if(dis[to[e]]>dis[que[h]]+1)
|
|
{
|
|
dis[to[e]]=dis[que[h]]+1;
|
|
if(!inq[to[e]])
|
|
que[t++]=to[e],inq[to[e]]=true;
|
|
}
|
|
}
|
|
int main()
|
|
{
|
|
int n,m;
|
|
while(scanf("%d",&n),n)
|
|
{
|
|
memset(adj,0,sizeof(adj));
|
|
ecnt=0;
|
|
char buf[12];
|
|
for(int i=0; i<n; i++)
|
|
scanf("%s",buf),v[i]=getHash(buf);
|
|
sort(v,v+n);
|
|
scanf("%d",&m);
|
|
for(int i=0; i<m; i++)
|
|
{
|
|
scanf("%s",buf);
|
|
int idx1=lower_bound(v,v+n,getHash(buf))-v;
|
|
scanf("%s",buf);
|
|
int idx2=lower_bound(v,v+n,getHash(buf))-v;
|
|
addEdge(idx1,idx2),addEdge(idx2,idx1);
|
|
}
|
|
int ans=0;
|
|
for(int i=0; i<n; i++)
|
|
{
|
|
spfa(i);
|
|
for(int j=0; j<n; j++)
|
|
if(i!=j&&dis[j]>ans)
|
|
ans=dis[j];
|
|
}
|
|
if(ans>0x20000000) ans=-1;
|
|
printf("%d\n",ans);
|
|
}
|
|
return 0;
|
|
}
|