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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    long long n,m,s;
    cin>>n>>m>>s;
    vector<pair<long long, long long>> in;
    for (int i=0; i<m; i++) {
        long long l,r;
        cin>>l>>r;
        in.push_back({l,r});
    }

    sort(in.begin(), in.end());
    int ii = -1;
    for (int i=0; i<m; i++) {
        if (s < in[i].first || s > in[i].second) continue;
        ii = i;
        break;
    }
    long long pl = in[ii].first-1, pr = in[ii].second+1;
    for (int i=ii-1; i>=0; i--) if (pl == in[i].second) pl = in[i].first-1;
    for (int i=ii+1; i<m; i++) if (pr == in[i].first) pr = in[i].second+1;
    if (pl < 1) cout<<pr<<'\n';
    else if (pr > n) cout<<pl<<'\n';
    else if (s-pl > pr-s) cout<<pr<<'\n';
    else cout<<pl<<'\n';

    return 0;
}