题目,发到学术版是想让更多人看到。
对照着 wsx248 的题解写的,不知道为什么连样例都没过,求调 qwq
code:
#include<bits/stdc++.h>
using namespace std;
int t;
struct EdgeInfo{
int to,w;
};
int n,m;
vector<EdgeInfo> G[2031];
struct NodeMessage{
int pos; long long tme; int spd;
friend bool operator < (NodeMessage a,NodeMessage b){
return a.tme>b.tme;
}
};
int s[1031];
long long dis[1031][1031];
bool vis[1031][1031];
void dijkstra(){
memset(dis,0x3f,sizeof(dis));
memset(vis,0,sizeof(vis));
priority_queue<NodeMessage> pq;
pq.push({1,0,s[1]}),dis[1][s[1]]=0;
while(!pq.empty()){
int npos=pq.top().pos,nspd=pq.top().spd; pq.pop();
if(vis[npos][nspd]) continue; vis[npos][nspd]=1;
for(EdgeInfo i:G[npos]){
if(dis[i.to][nspd]>dis[npos][nspd]+i.w*1ll*nspd)
dis[i.to][nspd]=dis[npos][nspd]+i.w*1ll*nspd,
pq.push({i.to,dis[i.to][nspd],nspd});
if(dis[i.to][s[i.to]]>dis[npos][nspd]+i.w*1ll*nspd)
dis[i.to][s[i.to]]=dis[npos][nspd]+i.w*1ll*nspd,
pq.push({i.to,dis[i.to][s[i.to]],s[i.to]});
}
}
}
void sol(){
cin>>n>>m;
for(int i=1,u,v,w;i<=m;i++){
cin>>u>>v>>w;
G[u].push_back({v,w});
G[v].push_back({u,w});
}
for(int i=1;i<=n;i++) cin>>s[i];
dijkstra();
long long ans=1e18;
for(int i=1;i<=n;i++) ans=min(ans,dis[n][s[i]]);
cout<<ans<<'\n';
}
signed main(){
cin>>t;
while(t--) sol();
return 0;
}