ll@n,@a[n],@b[];
Heap<pair<ll,pair<ll,ll>>>h;
h.malloc(n);
ll mn=1d9,mx=0;
rep(i,n){
	ll x=min(a[i],b[i]);
	h.push({x,{abs(a[i]-b[i])>>1,2}});
	mn<?=x;
	mx>?=x;
}
ll z=mx-mn;
while(true){
	auto c=h.pop();
	if(c.second.second==0){
		break;
	}
	ll x=c.first+c.second.first;
	h.push({x,{c.second.first,c.second.second-1}});
	mx>?=x;
	z<?=mx-h.top().first;
}
wt(z);