#include <fstream>

using namespace std;

const int MAXM = 100000;

struct Delete {
  int x, y;
} v[MAXM];

int main()
{
    int n, m, k;
    ifstream fin("stergeri.in");
    fin >> n >> m >> k;
    for (int i = 0; i < m; ++i)
      fin >> v[i].x >> v[i].y;
    fin.close();
    for (int i = m - 1; i >= 0; --i)
      if (k >= v[i].x)
        k += v[i].y - v[i].x + 1;
    ofstream fout("stergeri.out");
    fout << k << '\n';
    fout.close();
    return 0;
}