#include <fstream>
using namespace std;
ifstream in("stergeri.in");
ofstream out("stergeri.out");

#define NMAX 100010

int n, m, k, q1[NMAX], q2[NMAX];

int main()
{
    int i;
    in>>n>>m>>k;
    for (i = 1;i <= m;++i)
        in>>q1[i]>>q2[i];
    for (i = m;i >= 1;--i)
        if (k >= q1[i])
            k += q2[i] - q1[i] + 1;
    out<<k;
}