#include <fstream>
using namespace std;

const int DIM = 1000001;
int n, q, k, x, y;

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

pair<int, int> M[1000001];

int main()
{
    fin >> n >> q >> k;
    for(int i = 1; i <= q; ++i)
        fin >> M[i].first >> M[i].second;

    for(int i = q; i >= 1; --i)
    {
        if(k > M[i].first)
            k += M[i].second - M[i].first + 1;
    }
    fout << k;
}