#include<fstream>
using namespace std;
ofstream out("stergeri.out");
struct interval
{
	int x,y;
};
interval a[100001];
int n,m,k;
int main()
{
	ifstream in("stergeri.in");
	in>>n>>m>>k;
	for(int i=1;i<=m;i++)
		in>>a[i].x>>a[i].y;
	for(int i=m;i>=1;--i)
		if(a[i].x<=k)
			k+=a[i].y-a[i].x+1;
		out<<k;
	return 0;
}