#include<stdio.h>

typedef struct {
  int left, right;
} interval;

int N, M, K;

interval a[100000];

int main() {

  FILE *f = fopen("stergeri.in", "r");
  FILE *g = fopen("stergeri.out", "w");
  
  fscanf(f, "%d%d%d", &N, &M, &K);
  
  for (int i = 0; i < M; i++) {
    fscanf(f, "%d%d", &a[i].left, &a[i].right);
  }
  
  for (int i = M - 1; i >= 0; i--) {
    if (K >= a[i].left) {
      K += a[i].right - a[i].left + 1;
    }
  }

  fprintf(g, "%d\n", K);
  fclose(f);
  fclose(g);
  
  return 0;
  
}