#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define ll long long
const ll INF = 1e18;
ll D[100005];
ll D2[100005];
ll prevv[100005];
ll visited[100005];
ll tempp[100005];
vector<pair<ll, ll>> jalur[100005];
void priorityQueue(int jumlahKota, ll D[], ll start, ll prevv[])
{
for(int i = 1; i <= jumlahKota; i++)
{
D[i] = INF;
visited[i] = 0;
}
D[start] = 0;
priority_queue<pair<ll, ll>,vector<pair<ll, ll>>,greater<pair<ll, ll>>> q;
q.push({0,start});
while(!q.empty())
{
pair<ll, ll> p = q.top();
q.pop();
ll u = p.second, dist = p.first;
// if(dist > D[u]) continue;
if(visited[u] == 1)continue;
visited[u] = 1;
for(pair<ll, ll> pr : jalur[u])
{
// cout << pr.first << " " << pr.second << endl;
ll v = pr.first;
ll next_dist = dist + pr.second;
if(next_dist < D[v])
{
D[v] = next_dist;
q.push({next_dist,v});
prevv[v] = u;
}
}
}
}
int main()
{
int jumlahKota, jumlahJalan, ibuMrit, ibuRat, asal, tujuan;
cin >> jumlahKota >> jumlahJalan;
cin >> ibuMrit >> ibuRat;
cin >> asal >> tujuan;
for(int i = 0; i < jumlahKota; i++)
{
D2[i] = 0;
D[i] = 0;
prevv[i] = -1;
}
for(int i = 0; i < jumlahJalan; i++)
{
ll a, b, c;
cin >> a >> b >> c;
jalur[a].pb({b, c});
jalur[b].pb({a, c});
}
priorityQueue(jumlahKota, D2, asal, tempp);
ll absres = D2[tujuan];
cout << absres << endl;
return 0;
}
