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#include<cstring>
#include<cstdio>
#include<cmath>
#include<queue>
#include<algorithm>
#define ll long long
#define INF 1000000000
#define re register
using namespace std;
long long ()
{
register long long x = 0,f = 1;register char ch;
ch = getchar();
while(ch > '9' || ch < '0'){if(ch == '-') f = -f;ch = getchar();}
while(ch <= '9' && ch >= '0'){x = x * 10 + ch - 48;ch = getchar();}
return x * f;
}
long long n,m,u,v,s,ans,x,y,z,l,r,mid,cnt,flag,f[100005],d[100005],dis[100005],vis[100005];
struct 大专栏 题解 P1951 【收费站_NOI导刊2009提高（2）】s="title">edge{
long long to,nex,w;
}e[1000005];
struct node{
long long k,dis;
bool operator < (const node &x) const{return x.dis < dis;}
};
void add(long long x,long long y,long long z)
{
e[++cnt].to = y;
e[cnt].nex = d[x];
e[cnt].w = z;
d[x] = cnt;
}
priority_queue<node> que;
void dij()
{
while(!que.empty()) que.pop();
que.push((node){u,0});
while(!que.empty())
{
node u = que.top();
que.pop();
if(vis[u.k]) continue;
vis[u.k] = 1;
if(f[u.k] > mid) continue;
for(register int i = d[u.k]; i; i = e[i].nex)
{
if(f[e[i].to] > mid) continue;
if(dis[e[i].to] > dis[u.k] + e[i].w)
{
dis[e[i].to] = e[i].w + dis[u.k];
if(!vis[e[i].to]) que.push((node){e[i].to,dis[e[i].to]});
}
}
}
}
bool check(long long Max)
{
if(f[u] > Max || f[v] > Max) return false;
memset(dis,0x7f,sizeof(dis));
memset(vis,0,sizeof(vis));
dis[u] = 0;
dij();
if(dis[v] <= s) flag = 1;
if(dis[v] <= s) return true;
return false;
}
struct EDGE{
long long x,y,z;
}E[1000005];
bool cmp(EDGE a, EDGE b)
{
if(a.x != b.x) return a.x < b.x;
if(a.y != b.y) return a.y < b.y;
return a.z < b.z;
}
int main()
{
n = read(); m = read(); u = read(); v = read(); s = read();
for(int i = 1; i <= n; i++) f[i] = read(),r = max(r,f[i]);
r++;
for(int i = 1; i <= m; i++)
{
E[i].x = read();
E[i].y = read();
E[i].z = read();
}
sort(E + 1, E + m + 1, cmp);
for(int i = 1; i <= m; i++)
if((E[i].x != E[i - 1].x || E[i].y != E[i - 1].y) && E[i].x != E[i].y)
add(E[i].x,E[i].y,E[i].z),add(E[i].y,E[i].x,E[i].z);
while(l < r)
{
mid = (l + r) >> 1;
if(check(mid)) r = mid;
else l = mid + 1;
}
if(flag == 0) printf("-1n");
else printf("%lldn",r);
return 0;
}
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