D-松鼠回家_2023河南萌新联赛第（一）场：河南农业大学 (nowcoder.com)

 

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=2e5+10;
map<int,int>a;
int n,m,st,ed,h;
struct node{int x,y;
};
vector<node>hh[N];
int dis[N],vis[N];
struct cmp{bool operator()(const node &a,const node &b){return a.y<b.y;}
};
void dij(int k){memset(dis,0x3f,sizeof(dis));memset(vis,0,sizeof(vis));priority_queue<node,vector<node>,cmp >q;q.push({st,0});dis[st]=0;while(q.size()){node now=q.top();q.pop();int st=now.x;if(a[st]>k)continue;if(vis[st])continue;vis[st]=1;for(auto it:hh[st]){if(a[it.x]>k)continue;if(dis[it.x]>dis[st]+it.y){dis[it.x]=dis[st]+it.y;q.push({it.x,dis[it.x]});}}}
}
bool check(int mid){dij(mid);if(dis[ed]-dis[st]<=h)return 1;else return 0;
}
signed main(){cin>>n>>m>>st>>ed>>h;for(int i=1;i<=n;i++){cin>>a[i];}while(m--){int x,y,z;cin>>x>>y>>z;hh[x].push_back({y,z});hh[y].push_back({x,z});}int l=max(a[st],a[ed]),r=1e7+10;while(l<=r){int mid=(l+r)/2;if(check(mid))r=mid-1;else l=mid+1;}if(check(l)==0)cout<<"-1"<<endl;else cout<<l<<endl;return 0;
}