FOR ELNUR

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

typedef long long ll;
#define pii pair<ll , ll>
#define _FastIO ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define MAXX 1005

ll n , x , y , s;

int main()
{
    _FastIO;
    cin >> n;
    vector<pair<ll ,ll> > v;
    for(ll i = 0; i < n; i++){
        cin >> x >> y;
        v.push_back({y , x});
    }
    cin >> s;
    sort(v.begin() , v.end());
    for(ll i = 0; i < n; i++){
        x = v[i].second;
        y = v[i].first;
        s -= x;
        if(s <= 0){
            cout << y << endl;
            return 0;
        }
    }
    return 0;
}