// Template
#include <bits/stdc++.h>
#define rep_override(x, y, z, name, ...) name
#define rep2(i, n) for (int i = 0; i < (n); ++i)
#define rep3(i, l, r) for (int i = (l); i < (r); ++i)
#define rep(...) rep_override(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define per(i, n) for (int i = (n) - 1; i >= 0; --i)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
constexpr int inf = 1001001001;
constexpr ll INF = 3003003003003003003;
template <typename T> inline bool chmin(T& x, const T& y) {if (x > y) {x = y; return 1;} return 0;}
template <typename T> inline bool chmax(T& x, const T& y) {if (x < y) {x = y; return 1;} return 0;}
struct IOSET {IOSET() {cin.tie(0); ios::sync_with_stdio(0); cout << fixed << setprecision(10);}} ioset;

// Main
int main() {
    int n, m, p, s, t;
    cin >> n >> m >> p >> s >> t;
    --s; --t;
    vector<vector<int>> g(2 * n);
    rep(i, m) {
        int u, v;
        cin >> u >> v;
        --u; --v;
        g[u].push_back(v + n);
        g[u + n].push_back(v);
        g[v].push_back(u + n);
        g[v + n].push_back(u);
    }
    
    auto bfs = [&](int start) -> vector<int> {
        vector<int> dist(2 * n, inf);
        queue<int> que;
        dist[start] = 0;
        que.push(start);
        while (not que.empty()) {
            int v = que.front();
            que.pop();
            for (int u: g[v]) {
                if (dist[u] != inf) continue;
                dist[u] = dist[v] + 1;
                que.push(u);
            }
        }
        return dist;
    };
    
    vector<int> s_dist = bfs(s), t_dist = bfs(t);
    vector<int> ans;
    rep(i, n) {
        if (p & 1) {
            if (s_dist[i + n] + t_dist[i] <= p || s_dist[i] + t_dist[i + n] <= p) ans.push_back(i);
        } else {
            if (s_dist[i] + t_dist[i] <= p || s_dist[i + n] + t_dist[i + n] <= p) ans.push_back(i);
        }
    }
    
    if (p & 1) {
        if (s_dist[t + n] > p) {
            cout << "-1\n";
            return 0;
        }
    } else {
        if (s_dist[t] > p) {
            cout << "-1\n";
            return 0;
        }
    }
    
    cout << ans.size() << "\n";
    for (int v: ans) cout << v + 1 << "\n";
    return 0;
}