二分加dijkstraWA了1,4两个点，dalao求助

顾小伍 @ 2019-08-27 09:49:57

by 顾小伍 @ 2019-08-27 10:07:59

#include<bits/stdc++.h>
using namespace std;
inline int read()
{
    register int r=0,f=1;
    register char e=getchar();
    while(!isdigit(e)){
        if(e=='-')
          f=-1;
        e=getchar();
    }
    while(isdigit(e))
      r=(r<<1)+(r<<3)+e-'0',e=getchar();
    return r*f;
}
const int maxd=10001,maxn=50001;
struct code{
    int next,to,w;
}edge[maxn*2];
struct node{
    int id,dep;
    node(int a=0,int b=0):id(a),dep(b){}
    bool operator<(node a)const{
      return dep>a.dep;
    }
};
int cost[maxd],cnt,fir[maxn*2],dis[maxd],n,m,hp;
bool in[maxd];
inline void add(int a,int b,int t){
    edge[++cnt].next=fir[a];
    edge[cnt].to=b;
    edge[cnt].w=t;
    fir[a]=cnt;
}
inline bool check(int arr){
    if(arr<cost[1] || arr<cost[n])
      return 0;
    memset(dis,0x7f,sizeof(dis));
    memset(in,0,sizeof(in));
    dis[1]=0;
    in[1]=true;
    priority_queue<node>que;
    que.push(node(1,0));
    while(!que.empty()){
        node s=que.top();
        que.pop();
        register int u=s.id,d=s.dep;
        in[u]=false;
        for(register int i=fir[u];i;i=edge[i].next){
            register int v=edge[i].to,w=edge[i].w;
            if(cost[v]>arr)
              continue;
            if(dis[v]>dis[u]+w){
                dis[v]=dis[u]+w;
                if(!in[v]){
                    in[v]=true;
                    que.push(node(v,dis[v]));
                }
            }
        }
    }
    if(dis[n]<=hp)
      return true;
    else 
      return false;
}
int main()
{
    n=read(),m=read(),hp=read();
    for(register int i=1;i<=n;i++)
        cost[i]=read();
    for(register int i=1;i<=m;i++)
    {
        register int a=read(),b=read(),c=read();
        add(a,b,c);
        add(b,a,c);
    }
    register bool ok=false;
    if(!check(0x7fffffff))
    {
        printf("AFK\n");
        exit(0);
    }
    register int l=0,r=1000000001,ans=0;
    while(l<r){
        register int mid=(l+r)>>1;
        if(check(mid))
          r=mid,ok=true,ans=mid;
        else
          l=mid+1;
    }
    if(!ok)
      printf("AFK\n");
    else
      printf("%d\n",ans);
    return 0;
}

by CreeperLordVader @ 2019-08-27 10:28:13

不开long long见祖宗