#include<bits/stdc++.h>
using namespace std;

namespace prim {
	signed edge[5010][5010];
	signed dis[5010];
	signed st[5010];
	int n;
	inline int prim() {
		int ret = 0; // 返回值（最小代价）
		for (int i = 0 ; i < n; ++i) {/*n-1条边*/
			int t = -1;
			for (int j = 1; j <= n ; ++j)
				if (!~st[j]) //未加入
					if (t == -1 || st[j] > st[t])
						t = j;
			if (i && 0x3f3f3f3f == dis[t]) {
				cout << "orz " << endl;
				return -1;
			}
			if (i) ret += dis[t];//选
			st[t] = 1;
			for (int j = 1; j <= n; ++j) {
				dis[j] = min(dis[j], edge[j][t]);
			}
		}
		cout << ret;
		return ret;
	}
	inline void add(int a, int b, int c) {
		edge[a][b] = min(edge[a][b], c);
		edge[b][a] = min(edge[b][a], c);
	}

	void main() {

		memset(dis, 0x3f, sizeof (dis) );
		memset(st, -1, sizeof(st));
		memset(edge, 0x3f, sizeof(edge));
		int m, x, y, z;
		cin >> n >> m;
		while (m-- && cin >> x >> y >> z) add(x, y, z);
		prim();
	}
};
namespace kruskal {
	struct edge {
		int a;
		int b;
		int w;
	} edges[20010];
	int fat[20010];
	int n, m;
	inline void add_mmmmmmmmm(int a, int b, int c, int f) {
		edges[f] = {a, b, c};
	}
	inline void init() {//初始化
		cin >> n >> m;
		int x, y, z;
		for (int i = 0; i < m; ++i)cin >> x >> y >> z, add_mmmmmmmmm(x, y, z, i); //输入
		sort(edges, edges + m, [](edge a, edge b) {
			return a.w < b.w;
		});/*排序*/
		for (int i = 0; i < 20010; ++i)fat[i] = i;//初始化并查集
	}
	inline int find(int x) {
		return fat[x] == x ? x : fat[x] = find(fat[x]);//父亲
	}
//边 = 边（kruskal）
	int cnt = 0; //边数
	inline int add(int a) {//加边（kruskal）
		int x = find(edges[a].a);
		int y = find(edges[a].b);
		int w = edges[a].w;
		if (x ^ y)fat[x] = y, ++cnt;
		return x ^ y ? w : 0 ;
	}
	inline int kruskal() {
		int res = 0;
		for (int i = 0; i < m ; ++i)res += add(i); //加
		if (cnt < n - 1)return -1; //边数不到树
		return res;
	}
	void main() {
		init();
		int t = kruskal();
		if (~t)
			cout << t;
		else
			cout << "orz";
	}
}
int main() {
	kruskal::main();//79pts
	prim::main();//30pts
}