https://pintia.cn/problem-sets/994805046380707840/exam/problems/994805050709229568
输入样例：
7 5 4
1 2
2 3
3 1
4 5
5 6
1 4 5 7
输出样例：
2
6
4
0
#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef pair<LL,LL> PII;
const LL MAXN=1e18,MINN=-MAXN,INF=0x3f3f3f3f;
const LL N=1e6+10,M=2023;
const LL mod=100000007;
const double PI=3.1415926535;
#define endl '\n'
LL n,m,k,maxn=0,a[N];
LL dist[N];
vector<LL> v[N];
bool vis[N];
int bfs(int x)
{
memset(vis,false,sizeof vis);
memset(dist,0,sizeof dist);
queue<LL> q;
q.push(x);
dist[x]=0;
vis[x]=true;
while(q.size())
{
auto t=q.front();
q.pop();
for(int i=0;i<v[t].size();i++)
{
if(vis[v[t][i]]==true) continue;
vis[v[t][i]]=true;
q.push(v[t][i]);
dist[v[t][i]]=dist[t]+1;
maxn=max(maxn,dist[v[t][i]]);
}
}
}
int main()
{
cin.tie(0); cout.tie(0); ios::sync_with_stdio(false);
LL T=1;
//cin>>T;
while(T--)
{
cin>>n>>m>>k;
while(m--)
{
LL x,y;
cin>>x>>y;
v[x].push_back(y);
v[y].push_back(x);
}
while(k--)
{
LL x;
cin>>x;
if(v[x].size()==0)
{
cout<<"0"<<endl;
continue;
}
maxn=0;
bfs(x);
for(int i=1;i<=n;i++)
{
if(dist[i]==maxn)
{
cout<<i<<endl;
break;
}
}
}
}
return 0;
}