#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN = 200'000;
const int MAXX = 1'000'000'000;
const int INF = MAXN + MAXN * MAXX;
int n, m, x;
vector<pair<int, int>> e[MAXN * 2 + 5];
vector<pair<int, int>> ee[MAXN * 2 + 5];
int dis[MAXN * 2 + 5];
bool vis[MAXN * 2 + 5];
priority_queue<pair<int, int>> pq;
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m >> x;
    for (int i = 1; i <= n; i++)
    {
        e[i].push_back(make_pair(i + n, x));
        e[i + n].push_back(make_pair(i, x));
    }
    for (int i = 1; i <= m; i++)
    {
        int u, v;
        cin >> u >> v;
        e[u].push_back(make_pair(v, 1));
        e[v + n].push_back(make_pair(u + n, 1));
    }
    for (int i = 1; i <= n + n; i++)
        dis[i] = INF;
    dis[1] = 0;
    pq.push(make_pair(-0, 1));
    while (!pq.empty())
    {
        int u = pq.top().second;
        pq.pop();
        if (vis[u])
            continue;
        vis[u] = true;
        for (int i = 0; i < e[u].size(); i++)
        {
            int v = e[u][i].first;
            int w = e[u][i].second;
            if (dis[u] + w < dis[v])
            {
                dis[v] = dis[u] + w;
                pq.push(make_pair(-dis[v], v));
            }
        }
    }
    cout << min(dis[n], dis[n + n]);
    return 0;
}