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// Hallelujah, praise the one who set me free
// Hallelujah, death has lost its grip on me
// You have broken every chain, There's salvation in your name
// Jesus Christ, my living hope
#include <bits/stdc++.h>
using namespace std;

#define REP(i, s, e) for (int i = (s); i < (e); i++)
#define RREP(i, s, e) for (int i = (s); i >= (e); i--)
template <class T> inline bool mnto(T &a, T b) { return b < a ? a = b, 1 : 0; }
template <class T> inline bool mxto(T &a, T b) { return a < b ? a = b, 1 : 0; }

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
#define FI first
#define SE second
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
typedef tuple<int, int, int> iii;
#define ALL(_a) _a.begin(), _a.end()
#define SZ(_a) (int)_a.size()
#define pb push_back
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<ii> vii;
typedef vector<iii> viii;

#ifndef DEBUG
#define cerr                                                                   \
  if (0)                                                                       \
  cerr
#endif

const int INF = 1000000005;
const ll LINF = 1000000000000000005ll;
const int MAXN = 500005;

ll n;
int m;
ll s;
ll l[MAXN], r[MAXN];

int main() {
#ifndef DEBUG
  ios::sync_with_stdio(0), cin.tie(0);
#endif
  cin >> n >> m >> s;
  REP(i, 0, m) { cin >> l[i] >> r[i]; }
  ll rht = s;
  while (1) {
    bool delta = 0;
    REP(i, 0, m) {
      if (l[i] <= rht && rht <= r[i]) {
        delta = 1;
        rht = r[i] + 1;
      }
    }
    if (!delta) {
      break;
    }
  }
  if (rht == n + 1) {
    rht = LINF;
  }
  ll lft = s;
  while (1) {
    bool delta = 0;
    REP(i, 0, m) {
      if (l[i] <= lft && lft <= r[i]) {
        delta = 1;
        lft = l[i] - 1;
      }
    }
    if (!delta) {
      break;
    }
  }
  if (lft == 0) {
    lft = -LINF;
  }
  if (s - lft <= rht - s) {
    cout << lft << '\n';
  } else {
    cout << rht << '\n';
  }
  return 0;
}