#include <fstream>
#include <vector>
using namespace std;

ifstream f("stergeri.in");
ofstream g("stergeri.out");

vector< pair<int,int> > Q;
int n,m,k;

int main()
{
    f>>n>>m>>k;
    for(int i=1;i<=m;++i)
    {
        int x,y;
        f>>x>>y;
        Q.push_back(make_pair(x,y));
    }

    for(int i=m-1;i>=0;--i)
    {
        if(k >= Q[i].first) k+=Q[i].second-Q[i].first+1;
    }

    g<<k<<"\n";

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