#include <fstream>
#include <queue>
#include <algorithm>

#define ll long long

using namespace std;

ifstream cin("stergeri.in");
ofstream cout("stergeri.out");

const int MMAX = 1e5;

int n, m, k;
pair<int, int> a[MMAX + 1];

int main() {
    cin >> n >> m >> k;
    for(int i = 1; i <= m; i++) {
        cin >> a[i].first >> a[i].second;
    }

    for(int i = m; i >= 1; i--) {
        if(a[i].first <= k) {
            k = k - a[i].first + a[i].second + 1;
        }
    }
    cout << k << '\n';
    return 0;
}