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

typedef long long ll;

const int MAXN = 1e3 + 7;
pair<ll, ll> inters[MAXN];

int main() {
    ios_base::sync_with_stdio(0);
    ll n, m, s; cin >> n >> m >> s;
    for (int i = 0; i < m; ++i) {
        cin >> inters[i].first >> inters[i].second;
    }
    sort(inters, inters + m);
    int idx = 0;
    for (int i = 0; i < m; ++i) {
        if (inters[i].first <= s && inters[i].second >= s) {
            idx = i;
            break;
        }
    }
    int org = idx;
    ll l = inters[idx].first - 1;
    while (idx > 0 && inters[idx - 1].second == l) {
        l = inters[--idx].first - 1;
    }
    idx = org;
    ll r = inters[idx].second + 1;
    while (idx < m - 1 && inters[idx + 1].first == r) {
        r = inters[++idx].second + 1;
    }
    if (l == 0) cout << r << "\n";
    else if (r == n + 1) cout << l << "\n";
    else {
        if (s - l <= r - s) cout << l << "\n";
        else cout << r << "\n";
    }
}