#include <iostream>
#include <vector>
#include <algorithm>
#define maxn 10005
using namespace std;
int n, m;
namespace djs
{
int parent[maxn];
bool mark[maxn];
void init()
{
    for (int i = 0; i <= n; i++)
    {
        parent[i] = -1;
        mark[i] = false;
    }
}
int find(int x)
{
    if (parent[x] < 0)
        return x;
    else
        return parent[x] = find(parent[x]);
}
bool merge(int x, int y)
{
    x = find(x);
    y = find(y);
    if (x != y) // x与y不在一个连通块
    {
        if (mark[x] && mark[y]) // 两个连通块都有环
            return false;
        else
        {
            if (parent[x] > parent[y])
                swap(x, y);
            parent[x] += parent[y];
            parent[y] = x;
            mark[x] |= mark[y];
            return true;
        }
    }
    else // x与y在一个连通块
    {
        if(mark[x])
            return false;
        else // 这个连通块没有环，可以加这条边
        {
            mark[x] = true;
            return true;
        }
    }
}
}
struct edge
{
    int from, to, weight;
};
inline bool cmper(const edge &x, const edge &y) { return x.weight > y.weight; }
vector<edge> edges;
int main()
{
    while (true)
    {
        cin >> n >> m;
        if (n == 0 && m == 0)
            return 0;
        djs::init();
        edges.clear();
        int a, b, c;
        for (int i = 1; i <= m; i++)
        {
            cin >> a >> b >> c;
            edges.push_back((edge){a, b, c});
        }
        sort(edges.begin(), edges.end(), cmper);

        int ans = 0;
        for (int i = 0; i < edges.size(); i++)
        {
            if (djs::merge(edges[i].from, edges[i].to))
                ans += edges[i].weight;
        }
        cout << ans << endl;
    }
    return 0;
}