#include <fstream>
using namespace std;
ifstream fin("stergeri.in");
ofstream fout("stergeri.out");
int n, m, k, i, a[100001], b[100001];
int main()
{
    fin >> n >> m >> k;
    for (i = 1; i <= m; i++)
        fin >> a[i] >> b[i];
    for (i = m; i > 0; i--)
    {
        if (k >= a[i])
            k += b[i] - a[i] + 1;
    }
    fout << k;
    return 0;
}