p5304 [GXOI/GZOI2019]旅行者

分析

代码

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int inf = 1e17+7;
int d[100100],head[100100],nxt[1000100],to[1000100],w[1000100],cnt;
int x[500100],y[500100],z[500100],n,m,s,t,pos[100100],vis[100100];
inline void add(int x,int y,int z){
    nxt[++cnt]=head[x];
    head[x]=cnt;
    to[cnt]=y;
    w[cnt]=z;
}
priority_queue<pair<int,int> >q;
inline int dij(){
    memset(vis,0,sizeof(vis));
    for(int i=1;i<=t;i++)d[i]=inf;
    d[s]=0;
    q.push(make_pair(0,s));
    while(!q.empty()){
      int x=q.top().second;
      q.pop();
      if(vis[x])continue;
      vis[x]=1;
      for(int i=head[x];i;i=nxt[i])
        if(d[to[i]]>d[x]+w[i]){
          d[to[i]]=d[x]+w[i];
          q.push(make_pair(-d[to[i]],to[i]));
        }
    }
    return d[t];
}
signed main(){
    int T,i,j,k;
    scanf("%lld",&T);
    while(T--){
      int ans=inf;
      scanf("%lld%lld%lld",&n,&m,&k);
      for(i=1;i<=m;i++)scanf("%lld%lld%lld",&x[i],&y[i],&z[i]);
      s=n+1,t=n+2;
      for(i=1;i<=k;i++)scanf("%lld",&pos[i]);
      for(i=0;i<=17;i++){
        cnt=0;
        memset(head,0,sizeof(head));
        for(j=1;j<=m;j++)add(x[j],y[j],z[j]);
          for(j=1;j<=k;j++)
            if((1<<i)&pos[j]){
                add(s,pos[j],0);
          }else {
              add(pos[j],t,0);
          }
        ans=min(ans,dij());
        cnt=0;
        memset(head,0,sizeof(head));
        for(j=1;j<=m;j++)add(x[j],y[j],z[j]);
          for(j=1;j<=k;j++)
            if(!((1<<i)&pos[j])){
                add(s,pos[j],0);
          }else {
              add(pos[j],t,0);
          }
        ans=min(ans,dij());
      }
      printf("%lld
",ans);
    }
    return 0;
}
原文地址:https://www.cnblogs.com/yzxverygood/p/11611238.html