#include<stdio.h>
#define M 100001
struct intervale{
int i,j;
} a[M];
int k,i,n,m;
FILE *in,*out;

int main(){
in=fopen("stergeri.in","rt");
out=fopen("stergeri.out","wt");
fscanf(in,"%d%d%d",&n,&m,&k);
for(i=1;i-m-1;i++)
 fscanf(in,"%d%d",&a[i].i,&a[i].j);
for(;m;m--)
  if(k>=a[m].i)
   k+=a[m].j-a[m].i+1;
fprintf(out,"%d\n",k);
return 0;
}