#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define llu unsigned long long
#define ld double
#define llu unsigned long long
#define rep(i,x,y)  for(int i=int(x);i<int(y);++i)
#define For(i,x,y)  for(int i=int(x);i<=int(y);++i)
#define FOr(i,x,y)  for(int i=int(x);i>=int(y);--i)
#define pi acos(-1) 
#define mk make_pair
#define pa pair<ll,ll>
#define lf else if
#define IL inline
#define max(x,y)    ((x)<(y)?(y):(x))
#define min(x,y)    ((x)<(y)?(x):(y))
#define sqr(x)      ((x)*(x))
#define Mul(x,y)    ((x)=1LL*(x)*(y)%mod)
#define Add(x,y)    ((x)=((x)+(y))%mod)
#define Max(x,y)    ((x)=((x)<(y)?(y):(x)))
#define Min(x,y)    ((x)=((x)>(y)?(y):(x)))
#define E(x)        return writeln(x),0
#define LL			(long long)
#define p(x)        printf("~%lld~\n",LL(x))
#define pp(x,y)     printf("~~%lld %lld~~\n",LL(x),LL(y))
#define ppp(x,y,z)  printf("~~~%lld %lld %lld~~~\n",LL(x),LL(y),LL(z))
#define pppp(a,b,c,d)	printf("~~~%lld %lld %lld %lld\n",LL(a),LL(b),LL(c),LL(d))
#define f_in(x)     freopen(x".in","r",stdin)
#define f_out(x)    freopen(x".out","w",stdout)
#define open(x)     f_in(x),f_out(x)
#define fi first
#define se second
#define GuYue		puts("\nGuYueNa________________________________________________________________________________")
typedef complex<double> E;
namespace cqz{
#ifdef LOCAL
    struct _{_(){freopen("cf.in","r",stdin);}}_; 
#endif 
#define NEG 1
    static const int GYN=2333333;
    char SZB[GYN],*SS=SZB,*TT=SZB;
    inline char gc(){   if (SS==TT){  TT=(SS=SZB)+fread(SZB,1,GYN,stdin); if (SS==TT) return '\n';  }   return *SS++;    }
#if NEG
    inline ll read(){    ll x=0,g=1; char ch=gc();   for (;!isdigit(ch);ch=gc()) if (ch=='-') g=-1;  for (;isdigit(ch);ch=gc())  x=x*10-48+ch;   return x*g; }
    inline void write(ll x){    if (x<0) putchar('-'),x=-x;  if (x>=10)   write(x/10);    putchar(x%10+'0');  }
#else
    inline ll read(){    ll x=0; char ch=gc();   for (;!isdigit(ch);ch=gc());    for (;isdigit(ch);ch=gc())  x=x*10-48+ch;   return x;   }
    inline void write(ll x){    if (x>=10)   write(x/10);    putchar(x%10+'0');  }
#endif
    inline char readchar(){ char ch=gc();   for(;isspace(ch);ch=gc());  return ch;  }
    inline ll readstr(char *s){ char ch=gc();   int cur=0;  for(;isspace(ch);ch=gc());      for(;!isspace(ch);ch=gc())  s[cur++]=ch;    s[cur]='\0';    return cur; }
	void Print(long long *a,int s,int t){For(i,s,t)printf("%lld ",a[i]);}
	void Print(int *a,int s,int t){For(i,s,t)printf("%d ",a[i]);}
	void Print(char *a,int s,int t){For(i,s,t)putchar(a[i]);}
	void writeln(ll x){write(x);puts("");}
}using namespace cqz;
const ll N=200010;
struct dt{
	ll a,id;
};
bool operator <(dt a,dt b){return a.a==b.a?a.id<b.id:a.a<b.a;}
multiset<dt>s1,s2;
ll n,answ,tp,x[N],y[N],vis[N],pos;
ll get(){
	s1.clear();s2.clear();
	For(i,1,n)
		s1.insert((dt){y[i],i}),
		s2.insert((dt){-x[i],i}),vis[i]=0;
	ll ans=0,pos=0;
	For(i,1,n){
		if ((i^tp)&1){
			for(;vis[(*s1.begin()).id];)s1.erase(s1.find(*s1.begin()));
			dt tmp=*s1.begin();
			if (x[tmp.id]>pos)	ans+=abs(x[tmp.id]-pos),pos=x[tmp.id];
			lf (y[tmp.id]<pos)	ans+=abs(y[tmp.id]-pos),pos=y[tmp.id];
//			writeln(tmp.id);
			vis[tmp.id]=1;
		}else{
			for(;vis[(*s2.begin()).id];)s2.erase(s2.find(*s2.begin()));
			dt tmp=*s2.begin();
			if (x[tmp.id]>pos)	ans+=abs(x[tmp.id]-pos),pos=x[tmp.id];
			lf (y[tmp.id]<pos)	ans+=abs(y[tmp.id]-pos),pos=y[tmp.id];
//			writeln(tmp.id);
			vis[tmp.id]=1;
		}
	}return ans+abs(pos);
}
int main(){
//	f_in("cf");
//	f_out("work");
	n=read();
	For(i,1,n){
		x[i]=read(),y[i]=read();
		s1.insert((dt){-y[i],i});
		s2.insert((dt){x[i],i});
	}tp=0;
	ll ans1=get();
	tp=1;
	ll ans2=get();
	writeln(max(ans1,ans2));
}

Measured memory_bytes: 18048