#include <fstream>

using namespace std;

ifstream in("stergeri.in");
ofstream out("stergeri.out");
int n, m, k;
pair<int, int> v[100005];

int main()
{
    in>>n>>m>>k;

    for(int i = 1; i<=m; i++)
    {
        in>>v[i].first>>v[i].second;
    }

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

    out<<k;

    return 0;
}