#define IN "stergeri.in"
#define OUT "stergeri.out"
#define Nmax 100001
#include<fstream>
using namespace std;

int n,m,i,k,x,capat[2][Nmax];

void citire()
{ifstream fin(IN);
 
  fin>>n>>m>>k;
 for(i=1;i<=m;i++)
  fin>>capat[1][i]>>capat[2][i];
 
 }

void solve()
{ ofstream fout(OUT);
 for(i=m;i>=1;i--)
   {
    if(x>=capat[1][i]) x=x+capat[2][i]-capat[1][i]+1;
    }
 fout<<x;
 }



int main()
{
 

 citire();
 x=k;
 solve();
 return 0;
 }