#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

int main()
{
    ifstream f("stergeri.in");
    ofstream g("stergeri.out");
    int N, M, K;
    vector <pair <int,int> > del;
    f >> N >> M >> K;
    int x,y;
    for (int i=0; i<M; i++) {
        f >> x >> y;
        del.push_back(make_pair(x,y));
    }
    for (int i=M-1; i>=0 ; i--){
        if (K < del[i].first)
            continue;
        else K = K + del[i].second - del[i].first + 1;
    }
    g << K;
    return 0;
}