#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pb push_back
#define mp make_pair
#define fi first
#define se second

const int maxn = 40000;

int n, m, k;
vector<pair<int, int> > g[maxn + 1];
bool vis[maxn + 1];
vector<int> ans;

void dfs(int cur, int ok) {
    if(ok) {
        ans.pb(cur);
    }
    vis[cur] = true;
    for(pair<int, int> nei : g[cur]) {
        if(!vis[nei.fi]) {
            dfs(nei.fi, max(ok, nei.se));
        }
    }
}

void solve() {
    cin >> n >> m >> k;
    for(int i = 1; i <= m; i++) {
        int a, b;
        cin >> a >> b;
        if(i <= k) {
            g[a].pb(mp(b, 1));
            g[b].pb(mp(a, 1));
        } else {
            g[a].pb(mp(b, 0));
            g[b].pb(mp(a, 0));
        }
    }
    dfs(1, 0);
    sort(ans.begin(), ans.end());
    cout << (int) ans.size() << "\n";
    for(int x : ans) {
        cout << x << " ";
    }
    cout << "\n";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    solve();
    return 0;
}