#include <iostream>
#include <map>
#include <set>
#include <queue>
#include <cmath>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>
using namespace std;
#pragma warning (disable: 4996)

long long N, M, P, S, G;
long long A[1 << 18], B[1 << 18];
long long dist[1 << 18][2];
long long dist1[1 << 18][2], dist2[1 << 18][2];
vector<int> X[1 << 18];

void solve(int stt) {
	for (int i = 1; i <= N; i++) {
		dist[i][0] = (1 << 30);
		dist[i][1] = (1 << 30);
	}
	queue<pair<int, int>> Q; Q.push(make_pair(stt, 0)); dist[stt][0] = 0;
	while (!Q.empty()) {
		int pos1 = Q.front().first;
		int pos2 = Q.front().second; Q.pop();
		for (int i : X[pos1]) {
			if (dist[i][pos2 ^ 1] > dist[pos1][pos2] + 1) {
				dist[i][pos2 ^ 1] = dist[pos1][pos2] + 1;
				Q.push(make_pair(i, (pos2 ^ 1)));
			}
		}
	}
}

int main() {
	cin >> N >> M >> P >> S >> G;
	for (int i = 1; i <= M; i++) {
		cin >> A[i] >> B[i];
		X[A[i]].push_back(B[i]);
		X[B[i]].push_back(A[i]);
	}

	// 最短距離
	solve(S); for (int i = 1; i <= N; i++) { dist1[i][0] = dist[i][0]; dist1[i][1] = dist[i][1]; }
	solve(G); for (int i = 1; i <= N; i++) { dist2[i][0] = dist[i][0]; dist2[i][1] = dist[i][1]; }

	// 判定
	vector<int> vec;
	for (int i = 1; i <= N; i++) {
		long long min_value = (1 << 30);
		if (P % 2 == 0) {
			min_value = min(min_value, dist1[i][0] + dist2[i][0]);
			min_value = min(min_value, dist1[i][1] + dist2[i][1]);
		}
		if (P % 2 == 1) {
			min_value = min(min_value, dist1[i][0] + dist2[i][1]);
			min_value = min(min_value, dist1[i][1] + dist2[i][0]);
		}
		if (min_value <= P) vec.push_back(i);
	}

	// 出力
	if (vec.size() == 0) { cout << "-1" << endl; }
	else {
		cout << vec.size() << endl;
		for (int i = 0; i < vec.size(); i++) cout << vec[i] << endl;
	}
	return 0;
}