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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
using ll = long long;

typedef pair<ll, ll> pll;

bool sort_operator(pll a, pll b) {
    return (a.second - a.first) < (b.second - b.first);
}

ll cal_best(vector<pll>& ranges, ll n, ll s) {
    sort(ranges.begin(), ranges.end(), sort_operator);

    ll candi1 = s - 1;
    bool ch = true;
    while(ch && candi1 >= 1) {
        ch = false;
        for(ll i = 0; i < ranges.size(); i++) {
            if (ranges[i].first <= candi1 && candi1 <= ranges[i].second) {
                ch = true;
                candi1 = ranges[i].first - 1;
                break;
            }
        }
    }
    
    ll candi2 = s + 1;
    ch = true;
    while(ch && candi2 <= n) {
        ch = false;
        for(ll i = 0; i < ranges.size(); i++) {
            if (ranges[i].first <= candi2 && candi2 <= ranges[i].second) {
                ch = true;
                candi2 = ranges[i].second + 1;
                break;
            }
        }
    }

    if (candi1 < 1) return candi2;
    if (candi2 > n) return candi1;
    
    if(abs(s - candi1) <= abs(candi2 - s)) return candi1;
    else return candi2;
}

int main() {
    ll n, m, s;
    cin >> n >> m >> s;
    
    vector<pll> ranges(m);
    for (ll i = 0; i < m; i++) {
        cin >> ranges[i].first >> ranges[i].second;
    }
    
    cout << cal_best(ranges, n, s) << "\n";
    return 0;
}