#include <cstdio>

int a[100000], b[100000];

int min(int a, int b) {
  if(a < b) return a;
  return b;
}

int main() {
  int n, m, k;
  FILE *fin = fopen("stergeri.in", "r");
  fscanf(fin, "%d%d%d", &n, &m, &k);
  for(int i = 0; i < m; ++i)
    fscanf(fin, "%d%d", &a[i], &b[i]);
  fclose(fin);
  for(int i = m - 1; i >= 0; --i)
    if(a[i] <= k)
      k = k + b[i] - a[i] + 1;
  FILE *fout = fopen("stergeri.out", "w");
  fprintf(fout, "%d", k);
  fclose(fout);
  return 0;
}