#include<bits/stdc++.h>
using namespace std;
#define int long long 
int n;
struct node{
	int x,y,z;
}c[400400];
int id,ans;
int fa[200200];
int used[200200][2];
pair<int,int>a[200200],b[200200];
bool cmp(pair<int,int> x,pair<int,int> y){
	return x.first>y.first;
}
int ct[200200],pre[200200],suf[200200],aa[200200],bb[200200];
signed main(){
	cin>>n;
	for (int i=1,x,y;i<=n;i++)
	cin>>x>>y,a[i]={x,i},b[i]={y,i},aa[i]=x,bb[i]=y;
	sort(a+1,a+n+1,cmp);
	sort(b+1,b+n+1,cmp);
	int ta=1,tb=1;
	for (int i=1;i<=n;i++){
		if(tb<=n&&(ta>n||a[ta].first<b[tb].first))ans+=b[tb].first,ct[b[tb].second]--,tb++;
		else ans+=a[ta].first,ct[a[ta].second]++,ta++;
	}
	bool fl=1;
	for (int i=1;i<=n;i++)
	if(ct[i]==0)fl=0;
	if(fl==1&&ta<=n&&tb<=n){
		for (int i=1;i<=n;i++){
			pre[i]=pre[i-1];
			if(ct[i]>0)pre[i]=max(pre[i],bb[i]);
			if(ct[i]<0)pre[i]=max(pre[i],aa[i]);
		}
		for (int i=n;i>=1;i--){
			suf[i]=suf[i+1];
			if(ct[i]>0)suf[i]=max(suf[i],bb[i]);
			if(ct[i]<0)suf[i]=max(suf[i],aa[i]);
		}
		int tmp=-1e9;
		for (int i=1;i<=n;i++)
		if(ct[i]>0)tmp=max(tmp,max(pre[i-1],suf[i+1])-aa[i]);
		else if(ct[i]<0)tmp=max(tmp,max(pre[i-1],suf[i+1])-bb[i]);
		ans+=2*tmp;
	}
	for (int i=ta;i<=n;i++)ans-=a[i].first;
	for (int i=tb;i<=n;i++)ans-=b[i].first;
	int sum=0;
	for (int i=1;i<=n;i++)
	sum+=aa[i]-bb[i];
	ans=max(ans,sum);sum=0;
	for (int i=1;i<=n;i++)
	sum+=bb[i]-aa[i];
	cout<<max(sum,ans)<<"\n";
}