#include <bits/stdc++.h>
 
using namespace std;
 
ifstream fin("stergeri.in");
ofstream fout("stergeri.out");
 
int main() {
    ios::sync_with_stdio(false);

	int n, m, k; fin >> n >> m >> k;

	vector < pair < int, int > > v(m);
	for (auto &x: v) fin >> x.first >> x.second;

	for (int i = m - 1; i >= 0; --i) {
		if (v[i].first <= k) {
			k += (v[i].second - v[i].first + 1);
		}
	}

	fout << k;
    return 0;
}