#include <fstream>
using namespace std;

ifstream cin("stergeri.in");
ofstream cout("stergeri.out");

int n, m, x, y, k, i;
struct INTERVAL
{
    int pr,dl;
}v[100001];

int main(){
    cin >> n >> m >> k;
    for(i = 1; i <= m; i++){
        cin >> v[i].pr>> v[i].dl;
    }
    for(i = m; i >= 1; i--){
        if(k >= v[i].pr){
            k += v[i].dl - v[i].pr + 1;
        }
    }
    cout<< k;
    return 0;
}