#include <iostream>
#include <fstream>
#include <vector>
#include <map>
#include <utility>
#include <queue>

#define UNDEF (-1)

using namespace std;

struct edge_t { int s, t, c; };

struct cand_t {
  int t, c;
public:
  cand_t(int t, int c) : t(t), c(c) { }
  cand_t(void) { }
public:
  bool operator <(const cand_t &other) const {
    if(c != other.c) return c > other.c;
    if(t != other.t) return t < other.t;
    return false;
  }
};

int main(void)
{
  ifstream fin("almost.in");
  int n, m, k;

  bool crflag = false;

  while(fin >> n >> m >> k) {
    if(n == 0 && m == 0 && k == 0) break;

    vector< map<int,int> > v1(n);
    vector< map<int,int> > v2(n);
    vector<edge_t> e(m);

    for(int i = 0; i < m; i++) {
      fin >> e[i].s >> e[i].t >> e[i].c;
      (e[i].s)--;
      (e[i].t)--;
      v1[e[i].s].insert(make_pair(e[i].t, e[i].c));
      v2[e[i].t].insert(make_pair(e[i].s, e[i].c));
    }

    vector<int> cost1(n, UNDEF);
    int rest1 = n;
    vector<int> cost2(n, UNDEF);
    int rest2 = n;

    priority_queue<cand_t> cue1;
    cue1.push(cand_t(0, 0));

    while(!cue1.empty()) {
      cand_t cand = cue1.top();
      cue1.pop();

      if(cost1[cand.t] != UNDEF) continue;
      cost1[cand.t] = cand.c;
      if(--rest1 <= 0) break;
      map<int,int> &adj = v1[cand.t];

      for(map<int,int>::iterator p = adj.begin(); p != adj.end(); p++) {
	if(cost1[p->first] == UNDEF) {
	  cue1.push(cand_t(p->first, cand.c + p->second));
	}
      }
    }

    priority_queue<cand_t> cue2;
    cue2.push(cand_t(n - 1, 0));

    while(!cue2.empty()) {
      cand_t cand = cue2.top();
      cue2.pop();

      if(cost2[cand.t] != UNDEF) continue;
      cost2[cand.t] = cand.c;
      if(--rest2 <= 0) break;
      map<int,int> &adj = v2[cand.t];

      for(map<int,int>::iterator p = adj.begin(); p != adj.end(); p++) {
	if(cost2[p->first] == UNDEF) {
	  cue2.push(cand_t(p->first, cand.c + p->second));
	}
      }
    }

    vector<int> ans;

    for(int i = 0; i < m; i++) {
      if(cost1[e[i].s] == UNDEF || cost2[e[i].t] == UNDEF)
	continue;
      if(cost1[e[i].s] + e[i].c + cost2[e[i].t] <= cost1[n - 1] + k)
	ans.push_back(i);
    }

    if(crflag) cout << endl;
    crflag = true;

    cout << ans.size() << endl;
    for(int i = 0; i < ans.size(); i++)
      cout << ans[i] + 1 << endl;
  }
}