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#include <bits/stdc++.h>
using namespace std;

#define FOR(i,p,q) for(int i=(p); i<=(q); ++i)
#define ROF(i,p,q) for(int i=(p); i>=(q); --i)
#define REP(i,q) for(int i=0; i<(q); ++i)
#define pb push_back
#define as assign
#define rz resize
#define Co const
#define all(X) X.begin(), X.end()
#define rall(X) X.rbegin(), X.rend()
#define sz(X) (int)(X.size())
#define ckmax(a,b) a=max(a,b)
#define ckmin(a,b) a=min(a,b)
#define V vector
typedef long long ll;
typedef mt19937_64 mt;
#ifndef UNCLE
 typedef basic_string<bool> vb;
 typedef basic_string<int> vi;
 typedef basic_string<ll> vl;
#else
 typedef V<bool> vb;
 typedef V<int> vi;
 typedef V<ll> vl;
#endif

ll N,K;
int M;
struct RG{ll p,q;};
V<RG> rgs;

void Input(){
    cin>>N>>M>>K;
    ll p,q;
    REP(_,M) cin>>p>>q, rgs.pb({p,q});
    sort(all(rgs),[](Co RG &a, Co RG &b){return a.p<b.p;});
}
void Solve(){
    RG rsRg=rgs[0];
    FOR(i,1,M-1){
        if(rgs[i-1].q+1==rgs[i].p) rgs[i].p=rgs[i-1].p;
        if(rgs[i].p<=K&&K<=rgs[i].q) rsRg=rgs[i];
    }
    ++M;--M;
    if((rsRg.p!=1&&K-rsRg.p<=rsRg.q-K)||rsRg.q==N) cout<<rsRg.p-1<<"\n";
    else cout<<rsRg.q+1<<"\n";
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);

    Input();
    Solve();
}