#include <climits>
#include <iostream>
#include <queue>
#include <utility>
#include <vector>

using namespace std;

vector<int> get_potentials(int begin, const vector<vector<pair<int, int> > > &edges_from)
{
    const int V = edges_from.size();
    priority_queue<pair<int, int> > q;
    vector<int> potentials(V, INT_MAX);
    q.push(make_pair(-0, begin));

    while (!q.empty()) {
        pair<int, int> c = q.top(); q.pop();
        if (potentials[c.second] != INT_MAX) continue;
        potentials[c.second] = -c.first;

        const vector<pair<int, int> > &n = edges_from[c.second];
        for (int i = 0; i < n.size(); i++)
            if (potentials[n[i].first] == INT_MAX)
                q.push(make_pair(c.first - n[i].second, n[i].first));
    }

    return potentials;
}

struct Road {
    int from, to, length;
    Road(int from, int to, int length) : from(from), to(to), length(length) {}
};

int main()
{
    for (int N, M, K; cin >> N >> M >> K, N || M || K; ) {
        vector<Road> roads;
        vector<vector<pair<int, int> > > roads_from(N); // <to, length>
        vector<vector<pair<int, int> > > roads_to(N); // <from, length>
        for (int i = 0; i < M; i++) {
            int from, to, length;
            cin >> from >> to >> length;
            from--, to--;
            roads.push_back(Road(from, to, length));
            roads_from[from].push_back(make_pair(to, length));
            roads_to[to].push_back(make_pair(from, length));
        }

        vector<int> answer; {
            const vector<int> l = get_potentials(0, roads_from);
            const vector<int> r = get_potentials(N-1, roads_to);
            const int shortest = l[N-1];
            for (int i = 0; i < M; i++)
                if (l[roads[i].from] != INT_MAX && r[roads[i].to] != INT_MAX &&
                    l[roads[i].from] + roads[i].length + r[roads[i].to] <= shortest + K)
                    answer.push_back(i+1);
        }

        static bool first = true;
        if (first) first = false;
        else cout << endl;
        cout << answer.size() << endl;
        for (int i = 0; i < answer.size(); i++)
            cout << answer[i] << endl;
    }
    return 0;
}