#include<bits/stdc++.h>
using namespace std;
using ll=long long;
template<typename T>
ostream& operator << (ostream &out,const vector<T>&x){
	if(x.empty())return out<<"[]";
	out<<'['<<x[0];
	for(int len=x.size(),i=1;i<len;i++)out<<','<<x[i];
	return out<<']';
}
template<typename T>
vector<T> ary(const T *a,int l,int r){
	return vector<T>{a+l,a+1+r};
}
template<typename T>
void debug(T x){
	cerr<<x<<'\n';
}
template<typename T,typename ...S>
void debug(T x,S ...y){
	cerr<<x<<' ',debug(y...);
}
const int N=1e5+10,M=5e5+10,K=40,INF=1e9;
int n,m,q,cnt;
struct edges{
	int u,v,w;
}e[M],t[K*K];
struct opts{
	int x,y;
}o[K];
int k,fa[N],id[N],cur[M];
bool cmp(int x,int y){
	return e[x].w<e[y].w;
}
int find(int x){
	return fa[x]==x?x:fa[x]=find(fa[x]);
}
bool merge(int x,int y){
	x=find(x),y=find(y);
	if(x==y)return 0;
	else return fa[x]=y,1;
}
int main(){
	scanf("%d%d",&n,&m);
	iota(fa,fa+1+n,0);
	for(int i=1;i<=m;i++){
		scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].w);
		merge(e[i].u,e[i].v);
	}
	for(int i=2;i<=n;i++){
		if(find(i)^find(1))puts("-1"),exit(0);
	}
	iota(fa,fa+1+n,0);
	scanf("%d",&q);
	for(int i=1;i<=q;i++){
		scanf("%d%d",&o[i].x,&o[i].y);
		merge(e[o[i].x].u,e[o[i].x].v);
		merge(e[o[i].y].u,e[o[i].y].v);
	}
	iota(cur,cur+1+m,0);
	sort(cur+1,cur+1+m,cmp);
	int sum=0;
	vector<pair<int,int> >E;
	for(int x=1,i;i=cur[x],x<=m;x++){
		if(merge(e[i].u,e[i].v)){
			sum+=e[i].w;
			E.push_back({e[i].u,e[i].v});
		}
	}
	iota(fa,fa+1+n,0);
	for(auto et:E)merge(et.first,et.second);
	for(int i=1;i<=n;i++){
		if(!id[find(i)])id[find(i)]=++k;
		id[i]=id[find(i)];
	}
	for(int x=1,i;i=cur[x],x<=m;x++){
		if(merge(e[i].u,e[i].v)){
			t[++cnt]=e[i];
		}
	}
	int ans=INF;
	// for(int i=1;i<=cnt;i++)debug(t[i].u,t[i].v);
	for(int S=0;S<(1<<q);S++){
		int res=sum*(n>1);
		iota(fa,fa+1+k,0);
		for(int i=0;i<q;i++){
			int x=S>>i&1?o[i+1].x:o[i+1].y;
			res+=e[x].w,merge(id[e[x].u],id[e[x].v]);
		}
		if(n>1)for(int i=1;i<=cnt;i++){
			if(merge(id[t[i].u],id[t[i].v])){
				res+=t[i].w;
			}
		}
		ans=min(ans,res);
	}
	cout<<ans<<endl;
	return 0;
}