#include <fstream>

using namespace std;
ifstream cin("stergeri.in");
ofstream cout("stergeri.out");
struct{
    int x, y;
}v[100001];
int n, m, k;
int main(){
    cin >> n >> m >> k;
    for (int i = 1; i <= m; i++)
        cin >> 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;
    }
    cout << k;
    return 0;
}