# include <fstream>
using namespace std;
    long long n, m, k, i, in, sf, elem, s, v[100001][2];
	int main (){
		ifstream f ("stergeri.in");
		f>>n>>m>>k;
		elem=k;
		for (i=1;i<=m;++i){
			f>>v[i][0]>>v[i][1];
			s+=(sf-in+1);
			if (k>=in && k<=sf){//daca il sterge
				elem+=s;
			}
		}
		for (i=m;i;--i){
			if (v[i][0]<=elem){
				elem=elem+(v[i][1]-v[i][0]+1);
			}
		}
		ofstream g ("stergeri.out");
		g<<elem<<'\n';
		g.close ();
		return 0;
	}