#include <fstream>
#define MMAX 100000

using namespace std;

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

int x[MMAX + 1], y[MMAX + 1];

int main() {
  int n, m, k, i;
  cin >> n >> m >> k;
  for (i = 0; i < m; i++)
    cin >> x[i] >> y[i];
  for (i = m - 1; i >= 0; i--)
    if (k >= x[i])
      k += (y[i] - x[i] + 1);
  cout << k;
  return 0;
}