#include<iostream>
#include<cstdio>
#include<set>
#include<queue>
#define N 300000
using namespace std;
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
struct reads
{
	int num,data;
	bool operator < (const reads &t)const
	{
		return data!=t.data?data<t.data:num<t.num;
	}
};
int n,m,rt[N+1],st[N+1],leng,X[N+1],Y[N+1],Z[N+1],delta[N+1],tong[N+1],length;
bool used[N+1];
long long w[N+1];
set<reads>s[N+1];
priority_queue<int,vector<int>,greater<int>>q;
int find(int x)
{
	if (rt[x]==x) return x;
	return rt[x]=find(rt[x]);
}
void adder(int x)
{
	if (find(X[x])==find(Y[x])) return;
	if (s[find(X[x])].find((reads){x,(delta[x]+1)>>1})!=s[X[x]].end()) s[find(X[x])].erase((reads){x,(delta[x]+1)>>1});
	if (s[find(Y[x])].find((reads){x,(delta[x]+1)>>1})!=s[Y[x]].end()) s[find(Y[x])].erase((reads){x,(delta[x]+1)>>1});
	if (w[find(X[x])]+w[find(Y[x])]>=Z[x]) q.push(x);
	else delta[x]=Z[x]-w[find(X[x])]-w[find(Y[x])],s[find(X[x])].insert((reads){x,(delta[x]+1)>>1}),s[find(Y[x])].insert((reads){x,(delta[x]+1)>>1});
	return;
}
void solve(int x)
{
	length=0;
	while (!s[x].empty()&&(*s[x].begin()).data<=w[x]) tong[++length]=(*s[x].begin()).num,s[x].erase(s[x].begin());
	for (int i=1;i<=length;++i) adder(tong[i]);
	return;
}
void unionn(int x,int y)
{
	if (s[x].size()>s[y].size()) swap(s[x],s[y]);
	for (auto it:s[x]) s[y].insert(it);
	w[y]+=w[x],solve(y),rt[x]=y;
	return;
}
int main()
{
	int top;
	n=read(),m=read();
	for (int i=1;i<=n;++i) w[i]=read(),rt[i]=i;
	for (int i=1;i<=m;++i) X[i]=read(),Y[i]=read(),Z[i]=read(),adder(i);
	for (int i=1;i<=n;++i) solve(i);
	while (!q.empty())
	{
		top=q.top(),q.pop();
		if (find(X[top])==find(Y[top])) continue;
		st[++leng]=top,unionn(find(X[top]),find(Y[top]));
	}
	printf("%d\n",leng);
	for (int i=1;i<=leng;++i) printf("%d ",st[i]);
	puts("");
	return 0;
}