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/// UH Top
#include <bits/stdc++.h>
#define db(x)   cerr << #x << ':' << (x) << '\n';
#define all(v)  (v).begin(), (v).end()
#define allr(v) (v).rbegin(), (v).rend()
#define int     ll
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
// typedef __int128_t int128;
typedef pair<ll, ll> pii;
typedef pair<ld, ll> pdi;
typedef pair<ld, ld> pdd;
typedef pair<ld, pdd> pdp;
typedef pair<string, ll> psi;
typedef pair<ll, string> pls;
typedef pair<string, string> pss;
typedef pair<ll, pii> pip;
typedef pair<pii, pii> ppp;
// typedef complex<ld> point;
// typedef vector<point> polygon;
typedef vector<ll> vi;
// typedef pair<point, int> ppi;
#define prec(n)                                                                \
	cout.precision(n);                                                         \
	cout << fixed
const ll mod = (1e9 + 7);
const ld eps = (1e-9);
const ll oo = (ll)(1e9 + 5);
#define pi   acos(-1)
#define MAXN (ll)(1e6 + 5)

int32_t main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n, m, s;
	cin >> n >> m >> s;
	vector<pii> a(m);
	bool isIn = 0;
	vector<int> toTry;
	for (int i = 0; i < m; i++) {
		cin >> a[i].first >> a[i].second;
		if (a[i].first <= s && s <= a[i].second) {
			isIn = 1;
		}
		if (a[i].first > 1)
			toTry.push_back(a[i].first - 1);
		if (a[i].second < n)
			toTry.push_back(a[i].second + 1);
	}

	if (!isIn) {
		cout << s << "\n";
		return 0;
	}

	sort(all(toTry));
	int best = 2 * n;
	for (auto x : toTry) {
		bool ok = 1;
		for (auto p : a) {
			if (p.first <= x && x <= p.second) {
				ok = 0;
				break;
			}
		}
		if (!ok)
			continue;
		if (abs(best - s) > abs(x - s)) {
			best = x;
		}
	}

	cout << best << "\n";

	return 0;
}