#include<stdio.h>
char f[2000001];
long v1[100001],v2[100001];
int main()
{
	long n,m,k,i,num,left,poz;
	freopen("stergeri.in","r",stdin);
	freopen("stergeri.out","w",stdout);
	scanf("%ld%ld%ld",&n,&m,&k);
	for(i=1;i<=n;++i)
		f[i]=1;
	for(i=1;i<=m;i++)
		scanf("%ld%ld",&v1[i],&v2[i]);

	for(i=1;i<=m;i++)
	{
		num=v2[i]-v1[i]+1;
		left=v1[i];
		poz=1;
		while(left)
		{
			if(f[poz])
			left--;
			poz++;
		}
		poz--;
		while(num)
		{
			if(f[poz])
			{
				f[poz]=0;
				num--;
			}
			poz++;
		}
	}
	poz=1;

	while(k)
	{
		if(f[poz])
			k--;
		poz++;
	}

	poz--;
	printf("%ld",poz);
	fcloseall();
	return 0;
}