#include <fstream>

using namespace std;

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

int v1[100005], v2[100005];

int main() {
    int n, m, k, x, y;
    fin >> n >> m >> k;
    for(int i = 1; i <= m; i++) {
        fin >> v1[i] >> v2[i];
    }
    for(int i = m; i >= 1; i--) {
        if(k >= v1[i]) {
            k += (v2[i] - v1[i] + 1);
        }
    }
    fout << k;
    return 0;
}