#include <fstream>

using namespace std;

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

const int MMAX = 100000;

int n, m, k;

pair <int, int> v[1 + MMAX];

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