#include <stdio.h>
#define MAXM 100000
int st[MAXM], dr[MAXM];

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