#include <fstream.h>
int main(){
	unsigned long a[100000],n,x,y,i,j,k,m,z;
	ifstream in("stergeri.in");
	ofstream out("stergeri.out");

	in>>n>>m>>k;z=m;
	for(i=1;i<=n;i++)a[i]=i;z=m;
	for(i=0;i<z;i++){
		in>>x>>y;
		for(j=x;j<=y;j++)
			if(a[j])a[j]=0;
				else y++;
	}
	for(i=1;i<=n&&k;i++)
		if(a[i])k--;
	out<<a[i-1];
	return 0;
}