#include <fstream>
using namespace std;

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

int n, m, k, x[1 << 17], card[1 << 17];

void citire () {
	in >> n >> m >> k;
	for (int i = 1, y; i <= m; ++i) {
		in >> x[i] >> y;
		card[i] = y - x[i] + 1;
	}
}

void exe () {
	for (int i = m; i>= 1; --i) {
		if (k >= x[i]) {
			k += card[i];
		}
	}
}

int main () {
	citire ();
	
	exe ();
	
	out << k;
	
	return 0;
}