#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<ll,ll> pll;

int main(){
    cin.tie(0)->sync_with_stdio(0);
    ll n,m,s;
    cin >> n >> m >> s;
    vector<pll> segments;
    for(int i=0; i<m; ++i){
        ll l,r;
        cin >> l >> r;
        segments.push_back({l,r});
    }
    sort(segments.begin(),segments.end());
    vector<pll> merged_segments;
    merged_segments.push_back(segments.front());
    for(int i=1; i<m; ++i){
        if(segments[i].first == merged_segments.back().second+1)
            merged_segments.back().second = segments[i].second;
        else
            merged_segments.push_back(segments[i]);
    }
    for(auto &[l,r] : merged_segments){
        if(l<=s && s<=r){
            if(l==1)
                cout << r+1;
            else if(r==n)
                cout << l-1;
            else if(abs(s-l) <= abs(s-r))
                cout << l-1;
            else
                cout << r+1;
            return 0;
        }
    }
}