#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int,int>
#define pb push_back
#define fi first
#define se second
#define dd(x) cout<<#x<<" is "<<x<<endl;
const int N = 200005;
vector<pii>adj[N];
int x[N];
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n,m; cin>>n>>m;
int s,t,l,k; cin>>s>>t>>l>>k;
for(int i=0; i<m; i++){
int a,b,c; cin>>a>>b>>c;
adj[a].pb({b,c});
adj[b].pb({a,c});
}
int cnt=0, cnt1=0, f=0;
for(auto [i,d]: adj[s]){
x[i] = 1;
cnt++;
if(i==t) f=1;
}
for(auto [i,d]: adj[t]){
if(x[i]) f=1;
cnt1++;
}
if(f){
cout<<n*(n-1)/2;
return 0;
}
cout<<cnt+cnt1+1;
//dd(cnt)
//dd(cnt1)
return 0;
}
