int main()
{
	int i,n,t=0;
	double m;
	int a[50000],b[50000],mina=10001,maxb=0;
	scanf("%d",&n);
	for(i=0;i<n;i++)
	{scanf("%d %d",&a[i],&b[i]);}
	for(i=0;i<n;i++)
	{mina=(mina<a[i])?mina:a[i],maxb=(maxb>b[i])?maxb:b[i];}
	for(m=mina;m<=maxb;m=m+0.5)
	{	
		for(i=0;i<n;i++)
		{
			if((m>=a[i])&&(m<=b[i]))
			{t++;break;}
		}
	}
	if(t==(2*(maxb-mina+1)-1))
	{
		printf("%d %d",mina,maxb);
	}
	else printf("no");
	return 0;
}