#include<fstream>
#include<vector>
using namespace std;

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

vector<pair<int, int> > a;         // sirul intervalelor care trebuie sterse

int n, m, k;

int main()
{
    fin >> n >> m >> k;
    a.resize(m+1);                               
    for( int i = 1; i <= m; ++i )
         fin >> a[i].first >> a[i].second;
    for( int i = m; i >= 1; --i )
         if( a[i].first <= k )
         {
             int l = a[i].second - a[i].first + 1;                  // l = lungimea intervalului 
             k = k + l;
         }
    fout << k;          
    fin.close();
    fout.close();
    
    return 0; 
}