#include <bits/stdc++.h>

using namespace std;
int n,m,k;
vector <pair<int,int> > a;
pair <int,int> p;
int main()
{
    int i,j;
    ifstream cin("stergeri.in");
    ofstream cout("stergeri.out");
    cin >> n >> m >> k;
    for (i=0; i<m; i++)
    {
        cin >> p.first >> p.second;
        a.push_back(p);
    }
    for (i=m-1; i>=0; i--)
    {
        if (k>=a[i].first)
            k+=a[i].second-a[i].first+1;
    }
    cout << k;





    return 0;
}