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#include "bits/stdc++.h"
using namespace std;
#define all(x) x.begin(),x.end()
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << p.first << " " << p.second; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { string sep; for (const T &x : v) os << sep << x, sep = " "; return os; }
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#define ASSERT(...) 42
#endif
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pi;
const ll oo = 1e18;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    ll n; int m; ll s;
    cin >> n >> m >> s;
    vector<array<ll,2>> ivs(m);
    for(auto& [l,r] : ivs) {
        cin >> l >> r;
    }
    auto isfree = [&](ll x) {
        if(x<1 or x>n) return false;
        for(auto [l,r] : ivs) {
            if(l<=x and x<=r) return false;
        }
        return true;
    };
    pair<ll,ll> ans = {oo,oo};
    auto check = [&](ll x) {
        if(isfree(x)) {
            ans=min(ans,{abs(x-s),x});
        }
    };
    for(auto [l,r] : ivs) {
        check(l-1);
        check(r+1);
    }
    cout << ans.second << '\n';

}