#include <fstream>

using namespace std;

ifstream fin("stergeri.in");
ofstream fout("stergeri.out");

int N, M, K;

struct perechi
{
    int x, y;
};
perechi V[100005];

int main()
{
    fin >> N >> M >> K;
    for (int i = 1; i <= M; ++i)
        fin >> V[i].x >> V[i].y;

    for (int i = M; i >= 1; --i)
        if (K >= V[i].x)
            K += V[i].y - V[i].x + 1;

    fout << K << '\n';

    fin.close();
    fout.close();
    return 0;
}