#include<iostream>
#include<algorithm>
using namespace std;
int n,w,a,b,c;
int f[100001];
struct node{
	int u,v,bz;
}oh[100001];
int find(int x)
{
	if(f[x]==x) return f[x];
	return f[x]=find(f[x]);
}
bool cmp(node a,node b)
{
	return a.bz<b.bz;
}
int main()
{
	cin>>n>>w;
	for(int i=1;i<=w;i++)
	{
	    
		cin>>a>>b>>c;
		oh[i].u=a;
		oh[i].v=b;
		oh[i].bz=c;
		if(i<=n-1) 
		{
			cout<<-1<<endl;
			continue;
		}
		for(int j=1;j<=n;j++) f[j]=j;
		sort(oh+1,oh+i+1,cmp);
		int cnt=0,ans=0,fl=0;
		for(int j=1;j<=w;j++)
		{
			int fx=find(oh[j].u),fy=find(oh[j].v);
			if(fx!=fy)
			{
				f[fx]=fy;
				cnt++;
				ans+=oh[j].bz;
			}
			if(cnt==n-1) 
			{
				fl=1;
				break;
			}
		}
		if(fl==1) cout<<ans<<endl;
		else cout<<-1<<endl;
	}
}