#include <fstream>

using namespace std;

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

struct INTERVAL {
	int st, dr;
};

#define MMAX 100000

INTERVAL v[MMAX + 1];

int main() {
	int n, m, k, i;
	cin >> n >> m >> k;
	for (i = 1; i <= m; i++) {
		cin >> v[i].st >> v[i].dr;
	}
	for (i = m; i >= 1; i--) {
		if (k >= v[i].st) {
			k = k + v[i].dr - v[i].st + 1;
		}
	}
	cout << k;
}