#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define p(x,y) pair<ll,ll>(x,y)
#define BIT(i,x) ((x>>i)&1)
#define MASK(x) (1<<x)
#define ld long double
#define __builtin_popcount __builtin_popcountll
#define pll pair<ll,ll>
template<class T1,class T2>
bool maximize(T1 &x,T2 y)
{
if(x<y)
{
x=y;
return 1;
}
return 0;
}
template<class T1,class T2>
bool minimize(T1 &x,T2 y)
{
if(y<x)
{
x=y;
return 1;
}
return 0;
}
void online()
{
std::ios_base::sync_with_stdio(0);
cin.tie(0);
#ifdef thuc
freopen("input.INP","r",stdin);
freopen("output.OUT","w",stdout);
#else
#endif
}
const ll Mihacutephomaique=1e5+10;
priority_queue<pll> miha1;
ll n,k;
ll a[4][Mihacutephomaique];
int main()
{
online();
cin>>n;
ll lv=0,mh=0,ans=0;
for(int i=1;i<=2*n;i++)
{
ll x,y;
cin>>y>>x;
if(x<1)
{
ans+=1-x;
x=1;
}
if(x>1)
{
ans+=x-2;
x=2;
}
if(y>n)
{
ans+=y-n;
y=n;
}
if(y<1)
{
ans+=1-y;
y=1;
}
a[x][y]++;
}
for(int i=1;i<=2;i++)
{
for(int j=1;j<=n;j++)
{
a[i][j]--;
}
}
for(int j=1;j<=n;j++)
{
lv+=a[1][j];
mh+=a[2][j];
if((lv<0&&mh>0)||(lv>0&&mh<0))
{
if(abs(lv)<abs(mh))
{
mh+=lv;
ans+=abs(lv);
lv=0;
}
else
{
lv+=mh;
ans+=abs(mh);
mh=0;
}
}
ans+=abs(lv)+abs(mh);
}
cout<<ans;
}
