#include<bits/stdc++.h>
using namespace std;

//#define int long long
#define ls (p<<1)
#define rs (p<<1|1)
#define mid ((l+r)>>1)
#define all(_array) (_array).begin(),(_array).end()
#define msp(_array) memset(_array,0x3f,sizeof _array)
#define ms0(_array) memset(_array,0,sizeof _array)
#define msn(_array) memset(_array,-1,sizeof _array)
#define mc(_tar,_array) memcpy(_tar,_array,sizeof _tar)
#define Yes cout<<"Yes"<<endl
#define No cout<<"No"<<endl
#define YES cout<<"YES"<<endl
#define NO cout<<"NO"<<endl
#define TAK cout<<"TAK"<<endl
#define NIE cout<<"NIE"<<endl
#define OK cerr<<"OK"<<endl
#define pii pair<int,int>
#define endl '\n'

bool bg_memory;
mt19937 rnd(time(0));
int Case=1;
const int mod=1e9+7;
const int inf=2147483647;
const int bs=233;
const double eps=1e-6;
const int N=5e2+7,M=1e5+7;

template<class _t1,class _t2>inline void cmax(_t1 &a,_t2 b){a=a<b?b:a;}
template<class _t1,class _t2>inline void cmin(_t1 &a,_t2 b){a=a>b?b:a;}
inline int qp(int a,int b,int p=mod){int res=1;while(b){if(b&1)res=1ll*res*a%p;a=1ll*a*a%p;b>>=1;}return res;}
inline int sqrt(int x,int r){int l=0,ans=0;while(l<=r){if(1ll*mid*mid<=x) ans=mid,l=mid+1;else r=mid-1;}return ans;}

int n;
int x[N],y[N];
struct node{
    int dp,x,y;
}f[N][N];

void Main(){
    
    cin>>n;
    for(int i=1;i<=n;i++) cin>>x[i]>>y[i],f[i][i].x=x[i],f[i][i].y=y[i];
    for(int i=2;i<=n+1;i++){
        for(int j=0;j+i-1<=n;j++){
            f[j][j+i-1].x=min(f[j+1][j+i-1].x,x[j]);
            f[j][j+i-1].y=min(f[j+1][j+i-1].y,y[j]);
            f[j][j+i-1].dp=inf;
            for(int k=j;k<j+i-1;k++){
                cmin(f[j][j+i-1].dp,f[j][k].dp+f[k+1][j+i-1].dp
                +f[j][k].x+f[k+1][j+i-1].x
                +f[j][k].y+f[k+1][j+i-1].y
                -2*f[j][j+i-1].x-2*f[j][j+i-1].y);
            }
        }
    }
    cout<<f[0][n].dp<<endl;

    return;
}
string RdFile="";
bool en_memory;

signed main(){
    auto bg_clock=chrono::high_resolution_clock::now();
#ifdef ONLINE_JUDGE
    // freopen((RdFile+".in").c_str(),"r",stdin);
    // freopen((RdFile+".out").c_str(),"w",stdout);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    // cin>>Case;
    while(Case--) Main();
    auto en_clock=chrono::high_resolution_clock::now();
    auto duration_clock=chrono::duration_cast<chrono::microseconds>(en_clock-bg_clock);
    double duration_count=duration_clock.count()*0.001;
    double memory_used=(&en_memory-&bg_memory)/1024.0/1024;
    // cerr<<"Time:"<<duration_count<<"ms"<<endl;
    // cerr<<"Memory: "<<memory_used<<"MB"<<endl;
    return 0;
}