#include<fstream>
#include<deque>
using namespace std;
ifstream f("stergeri.in");
ofstream g("stergeri.out");
int n,k,q,i,x,y;
deque<pair<int,int> >coada;
int main()
{
    f>>n>>k>>q;
    for(i=1;i<=k;i++)
    {
        f>>x>>y;
        coada.push_back(make_pair(x,y));
    }
    while(!coada.empty())
    {
        if(q>=coada.back().first)
          q+=coada.back().second-coada.back().first+1;
        coada.pop_back();
    }
    g<<q;
    return 0;
}