#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
signed main() { 
  ios::sync_with_stdio(false); cin.tie(0);
  int n, m, p;
  cin >> n >> m >> p;
  int st, gol;
  cin >> st >> gol;
  st--;
  gol--;
  vector<vector<int>> g(n);
  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    u--;
    v--;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  vector<int> dist_s(n << 1, -1);
  vector<int> que = {st << 1};
  dist_s[st << 1] = 0;
  for (int i = 0; i < (int) que.size(); i++) {
    int cur = que[i] >> 1;
    int d = dist_s[que[i]] + 1;
    for (int j : g[cur]) {
      int nxt = (j << 1) + d % 2;
      if (dist_s[nxt] != -1) continue;
      dist_s[nxt] = d;
      que.push_back(nxt);
    }
  }
  vector<int> dist_g(n << 1, -1);
  que = {gol << 1};
  dist_g[gol << 1] = 0;
  for (int i = 0; i < (int) que.size(); i++) {
    int cur = que[i] >> 1;
    int d = dist_g[que[i]] + 1;
    for (int j : g[cur]) {
      int nxt = (j << 1) + d % 2;
      if (dist_g[nxt] != -1) continue;
      dist_g[nxt] = d;
      que.push_back(nxt);
    }
  }
  vector<int> ans;
  for (int i = 0; i < n; i++) {
    int c = i << 1;
    for (int u = 0; u < 2; u++) for (int v = 0; v < 2; v++) {
      if (dist_s[c + u] != -1 && dist_g[c + v] != -1 && (u + v) % 2 == p % 2 && dist_s[c + u] + dist_g[c + v] <= p) {
        ans.push_back(i);
        continue;
      }
    }
  }
  if (!ans.empty()) {
    cout << ans.size() << '\n';
    for (auto x : ans) cout << x + 1 << '\n';
  } else {
    cout << -1 << '\n';
  }
  return 0;
}