#include <fstream>
#include <vector>
#include <utility>
using namespace std;

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

	int n, m, k;
	f >> n >> m >> k;

	vector<pair<int, int>> v(m);

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

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

	g << k << endl;

	return 0; }