#include <fstream>
#include <iostream>
#include <sstream>
#include <queue> 
#include <vector>
#include <algorithm>

using namespace std;

ifstream f("stergeri.in");
ofstream g("stergeri.out");

int main() {
	int n, m, k;
	f >> n >> m >> k;
	std::vector< pair<int, int> > v;
	for(int i = 0; i < m; i++) {
		int x, y;
		f >> x >> y;
		v.push_back(make_pair(x, y));
	}

	reverse(v.begin(), v.end());

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

	g << k;
	return 0;
}