# include <fstream>
using namespace std;
ifstream f("stergeri.in");
ofstream g("stergeri.out");
struct pozitii
{
    int st, dr;
} p[100001];
int main()
{
    int n, m, k, i;
    f>>n>>m>>k;

    for (i=1; i<=m; i++)
        f>>p[i].st>>p[i].dr;

    for (i=m; i>=1; i--)
        if (k>=p[i].st)
            k+=(p[i].dr-p[i].st+1);
    g<<k;
    f.close();
    g.close();
    return 0;
}