#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N=500010;
map <pair <int,int>,int> mp;
set <int> S,T;
int A,B,C,f[N];
pair <int,int> ans[N];
bool check(int x,int y){
	return (A*min(x,y)+B*max(x,y))%C>=f[x]+f[y]; 
}
int query(int x,int y){
	if (x>y) swap(x,y);
	return mp.count(make_pair(x,y))?mp[make_pair(x,y)]:check(x,y);
}
int getpre(int x){
	set <int>::iterator itList=S.lower_bound(x);
	if (itList==S.begin()) itList=S.end();
	return *--itList;
}
int getnxt(int x){
	set <int>::iterator itList=S.upper_bound(x);
	if (itList==S.end()) itList=S.begin();
	return *itList;
}
void modify(int x){
	int pre=getpre(x),nxt=getnxt(x);
	if (query(x,pre)!=query(x,nxt)) T.insert(x);
	else if (T.find(x)!=T.end()) T.erase(x);
} 
int read(){
	int x=0,f=1;
	char ch=getchar();
	while (ch<'0' || ch>'9'){
		if (ch=='-') f=-f;
		ch=getchar();
	}
	while (ch>='0' && ch<='9'){
		x=x*10+ch-48;
		ch=getchar();
	}
	return x*f;
}
int solve(){
	if (T.empty()){
		set <int>::iterator itList1=S.begin(),itList2=itList1;
		int col=query(*itList1,*++itList2);
		for (;itList2!=S.end();itList1=itList2++){
			printf("%lld %lld\n",*itList1,*itList2);
		}
		return col;
	}
	int x=*T.begin(),pre=getpre(x),nxt=getnxt(x);
	int col=query(x,pre);
	S.erase(x);T.erase(T.begin());modify(pre);modify(nxt);
	int newcol=solve();
	printf("%lld %lld\n",x,col=newcol?pre:nxt);
	return newcol;
}
signed main(){
	int n=read(),m=read();
	for (int i=1;i<=m;++i){
		int x=read(),y=read();
		if (x>y) swap(x,y);
		mp[make_pair(x,y)]=read();
	}
	A=read(),B=read(),C=read();
	for (int i=1;i<=n;++i) f[i]=read();
	for (int i=1;i<=n;++i) S.insert(i);
	for (int i=1;i<=n;++i) modify(i);
	solve();
	return 0;
}