#include <bits/stdc++.h>

using namespace std;
#define rep(i,n) for (int i = 0; i < (int)(n); ++i)
#define rrep(i,n) for (int i = (int)(n-1); i >= 0; --i)
#define Rep(i,a,b) for (int i = a; i < b; ++i)
#define rRep(i,a,b) for (int i = a; i > b; --i)
#define fore(i,a) for(auto &i:a)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define Unique(v) v.erase(unique(v.begin(), v.end()), v.end());
#define Bit(x,i) (((x)>>(i))&1)
using ll = long long;
using vi = vector<int>;
using vll = vector<long long>;
using vvi = vector<vi>;
using vvll = vector<vll>;
using vb = vector<bool>;
using vs = vector<string>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
struct settings{settings(){ios_base::sync_with_stdio(0); cin.tie(0); cout<<fixed<<setprecision(15);};}settingss;
const double PI = acos(-1);
const int INF = 1001001001;
const ll LINF = 1001001001001001001LL;

vvi G(100100);
vvll d1(100100, vll(2, -1));
vvll dN(100100, vll(2, -1));

int main() {
  ll N, M, P; cin >> N >> M >> P;
  int s, g; cin >> s >> g; --s; --g;
  rep(i, M) {
    int u, v; cin >> u >> v; --u; --v;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  queue<int> que;
  que.push(s);
  d1[s][0] = 0;
  while(!que.empty()) {
    int nw = que.front(); que.pop();
    fore(nx, G[nw]) {
      if(d1[nx][0] == -1) {
        if(d1[nw][1] >= 0) {
          d1[nx][0] = d1[nw][1] + 1;
          que.push(nx);
        }
      }
      if(d1[nx][1] == -1) {
        if(d1[nw][0] >= 0) {
          d1[nx][1] = d1[nw][0] + 1;
          que.push(nx);
        }
      }
    }
  }
  que.push(g);
  dN[g][0] = 0;
  while(!que.empty()) {
    int nw = que.front(); que.pop();
    fore(nx, G[nw]) {
      if(dN[nx][0] == -1) {
        if(dN[nw][1] >= 0) {
          dN[nx][0] = dN[nw][1] + 1;
          que.push(nx);
        }
      }
      if(dN[nx][1] == -1) {
        if(dN[nw][0] >= 0) {
          dN[nx][1] = dN[nw][0] + 1;
          que.push(nx);
        }
      }
    }
  }
  vi ans;
  rep(i, N) {
    if(d1[i][0] >= 0 && dN[i][0] >= 0) {
      ll sum = d1[i][0] + dN[i][0];
      if(sum <= P && (P - sum)%2 == 0) {
        ans.push_back(i);
        continue;
      }
    }
    if(d1[i][0] >= 0 && dN[i][1] >= 0) {
      ll sum = d1[i][0] + dN[i][1];
      if(sum <= P && (P - sum)%2 == 0) {
        ans.push_back(i);
        continue;
      }
    }
    if(d1[i][1] >= 0 && dN[i][0] >= 0) {
      ll sum = d1[i][1] + dN[i][0];
      if(sum <= P && (P - sum)%2 == 0) {
        ans.push_back(i);
        continue;
      }
    }
    if(d1[i][1] >= 0 && dN[i][1] >= 0) {
      ll sum = d1[i][1] + dN[i][1];
      if(sum <= P && (P - sum)%2 == 0) {
        ans.push_back(i);
        continue;
      }
    }
  }
  int sz = ans.size();
  if(sz == 0) {
    cout << -1 << endl;
  } else {
    cout << sz << endl;
    rep(i, sz) {
      cout << ans[i]+1 << endl;
    }
  }
}