#include <fstream>
using namespace std;
ifstream f("stergeri.in");
ofstream g("stergeri.out");
int n,m,k,i,x,y,w[100200],wt[100200],s,p;
int main()
{
    f>>n>>m>>k;
    s=n;
    for(i=1; i<=m; i++)
    {
        f>>x>>y;
        w[i]=x;
        wt[i]=y-x;
        s=s-(y-x+1);
    }

   p=m;

    while (p>=1)
    {
   if (k>=w[p]) k+=wt[p]+1;
   p--;
    }
g<<k<<'\n';

    f.close();
    g.close();
    return 0;
}