Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"strings"
	"sort"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)
const INF = 0x7fffffff
func main() {
	scanner.Scan()
	n, _ := strconv.Atoi(scanner.Text())
	top := make([]int, 0)
	bottom := make([]int, 0)
	for i := 0; i < n; i++ {
		scanner.Scan()
		buf := strings.Split(scanner.Text(), " ")
		a, _ := strconv.Atoi(buf[0])
		b, _ := strconv.Atoi(buf[1])
		top = append(top, a)
		bottom = append(bottom, b)
	}
	dp := make([][]int, n+1)
	for i := range dp {
		dp[i] = make([]int, n+1)
	}
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			dp[i][j] = INF
		}
	}
	for j := 0; j < n; j++ {
		dp[0][j] = 0
	}
	for i := 1; i < n; i++ {
		for j := 0; j < n-i; j++ {
			tmp := make([]int, 0)
			for k := 0; k < i; k++ {
				tmp = append(tmp, dp[k][j] + dp[i - k - 1][j + k + 1] +top[j] * bottom[j + k] * top[j + k + 1] * bottom[j + i])
			}
			sort.Ints(tmp)
			dp[i][j] = tmp[0]
		}
	}
	fmt.Println(dp[n-1][0])
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

C++: 
#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <memory>
#include <string>

#include <algorithm>
#include <complex>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <vector>
#include <bitset>

using namespace std;

#ifdef _MSC_VER
#define __typeof__ decltype
#define strtok_r strtok_s
#endif

#define ITER(c)             __typeof__((c).begin())
#define FOREACH(it, c)      for (ITER(c) it=(c).begin(); it != (c).end(); ++it)
#define RITER(c)            __typeof__((c).rbegin())
#define RFOREACH(it, c)     for (RITER(c) it=(c).rbegin(); it != (c).rend(); ++it)
#define REP(i, n)           REPEAT(i, 0, n)
#define RREP(i, n)          RREPEAT(i, 0, n)
#define REPEAT(i, k, n)     for(int i = (k); i < (k+n); ++i)
#define RREPEAT(i, k, n)    for(int i = (k)+(n)-1; i >= (k); --i)
#define FROMTO(i,f,t)       for(int i = f; i < t; i++)
#define ALL(c)              (c).begin(), (c).end()
#define LLPOW(p1,p2)        ((ll)pow((double)(p1), (int)p2))
#define ESIZEOF(A)          (sizeof(A)/sizeof((A)[0]))
#define CIN_NO_SYNC         do { cin.tie(0); ios_base::sync_with_stdio(false); } while(0)
#define GETSTR(p)           fgets((p), sizeof(p), stdin)
#define CHOMP(p)            do{ char *_q = (p) + strlen(p)-1; if(*_q == '\n' || *_q == '\r') *_q = 0; } while(0)
#define FILL(m,v)           memset(m, v, sizeof(m))
#define mp                  make_pair
#define pb                  push_back
template<class _T> _T MAX(_T p1,_T p2){return (p1>p2)?p1:p2;} 
template<class _T> _T MIN(_T p1,_T p2){return (p1<p2)?p1:p2;} 
template <class _Tv> inline string join(const _Tv &v,string sep=" "){
    ostringstream s;FOREACH(it,v){if(it!=v.begin())s<<sep;s<<*it;};return s.str();
}

typedef long long ll;
typedef unsigned long long ull;
typedef double D;
typedef complex<D> P;
#define X real()
#define Y imag()
#define EPS (1e-9)
#define DEQ(p1,p2) (abs((p1)-(p2)) < EPS)

#ifdef _DEBUG
template<class _Tv> inline void _prfe(const char *_n,const _Tv _c,bool _p=false){
    ITER(_c) _it=_c.begin();
    if(_p){cout<<_n<<" = ["<<endl;for(;_it!=_c.end();++_it)cout<<"    "<<*_it<<endl;cout<<"]"<<endl; }
    else{cout<<_n<<" = [ "<<*_it++;for(;_it!=_c.end();++_it)cout<<", "<<*_it;cout<<" ]"<<endl; }
}
#define pf printf
#define pr(n) do{cout<<#n" = "<<(n)<<endl;}while(0)
#define prfe(n) _prfe(#n, n)
#define prfep(n) _prfe(#n, n, true)
#define dbgchk(n) do{if(n)throw;}while(0)
#else
#define pf(...) /* */
#define pr(...) /* */
#define prfe(...) /* */
#define prfep(...) /* */
#define dbgchk(...) /* */
#endif

map<vector<pair<int,int> >,int> m;

int solve(vector<pair<int,int> > &v){
    int n = v.size();
    int min = INT_MAX;
    if(n == 1) return 0;
    ITER(m) it = m.find(v);
    if(it != m.end()) return it->second;
    vector<pair<int,int> > v2(v.begin()+1, v.end());
    REP(i,n-1){
        v2[i].first = v[i].first;
        v2[i].second = v[i+1].second;
        int cost = v[i].first * v[i].second * v[i+1].first * v[i+1].second;
        min = MIN(min, cost + solve(v2));
        v2[i] = v[i];
    }
    m[v] = min;
    return min;
}

int main(){
    int n;
    cin >> n;
    vector<pair<int,int> > v;
    REP(i,n){
        int a,b;
        cin >> a >> b;
        v.pb(mp(a,b));
    }
    cout << solve(v) << endl;
    return 0;
}

C++: #include<iostream>
#include<vector>
#include<climits>

#define MAX 101
#define Inf (UINT_MAX-1)

typedef unsigned int uint;
using namespace std;

struct State{
	State():cost(Inf),bottom(1),top(1){}
	uint cost;
	uint bottom;
	uint top;
};

State m[MAX][MAX];

void CardOrder(vector<pair<uint, uint> > &vc){
	int n = vc.size();
	for(int i = 1; i <= n; ++i){
		m[i][i].cost = 0;
		m[i][i].top = vc[i-1].first;
		m[i][i].bottom = vc[i-1].second;
	}
	for(int l = 2; l <= n; ++l){
		for(int i = 1; i <= n - l + 1; ++i){
			for(int j = i; j < i + l; ++j){
				uint cost = m[i][j].cost + m[j+1][i+l-1].cost +
					m[i][j].top * m[i][j].bottom * m[j+1][i+l-1].top * m[j+1][i+l-1].bottom;
				if( m[i][i+l-1].cost > cost ){
					m[i][i+l-1].cost = cost;
					if( m[i][j].top * m[j+1][i+l-1].bottom < m[j+1][i+l-1].top * m[i][j].bottom ){
						m[i][i+l-1].top = m[i][j].top;
						m[i][i+l-1].bottom = m[j+1][i+l-1].bottom;
					}else{
						m[i][i+l-1].top = m[j+1][i+l-1].top;
						m[i][i+l-1].bottom = m[i][j].bottom;
					}
				}
			}
		}
	}
}

int main()
{
	int n;
	vector< pair<uint, uint> > vCards;
	
	cin >> n;
	for(int x = 0; x < n; ++x){
		int top, btm;
		cin >> top >> btm;

		vCards.push_back( make_pair(top, btm) );
	}
	
	CardOrder( vCards );
	cout << m[1][n].cost << '\n';
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#include<stack>
#include<queue>
#include<cstdio>
#include<climits>
#include<cmath>
#include<cstring>
#include<string>
#include<sstream>

#define f first
#define s second
#define mp make_pair

#define REP(i,n) for(int i=0; i<(int)(n); i++)
#define FOR(i,c) for(__typeof((c).begin()) i=(c).begin(); i!=(c).end(); i++)
#define ALL(c) (c).begin(), (c).end()

using namespace std;

typedef unsigned int uint;
typedef long long ll;

int main(){
  int n;
  scanf("%d",&n);
  vector<int> a(n),b(n);
  REP(i,n) scanf("%d%d",&a[i],&b[i]);
  int cost = 0;
  while(a.size() != 1){
    int t;
    int c = 0;
    REP(i,a.size()-1){
      int tmp = b[i]*a[i+1];
      if(tmp > c){
	t = i;
	c = tmp;
      }
    }
    //printf("t=%d\n",t);
    cost += a[t]*b[t]*a[t+1]*b[t+1];
    a[t+1] = a[t];
    a.erase(a.begin() + t);
    b.erase(b.begin() + t);
  }
  printf("%d\n",cost);
  return 0;
}

C++: #include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <queue>
#include <cstring>
#include <deque>
#include <cstdio>
#include <cmath>
#include <complex>

using namespace std;

#define reep(i,f,t) for(int i=f ; i<int(t) ; ++i)
#define rep(i,n) reep(i, 0, n) 

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;

const int INF = 1<<29;

int main()
{
	int n;
	scanf("%d", &n);
	
	vector<pii> cards(n);
	rep(i, n){
		scanf("%d%d", &cards[i].first, &cards[i].second);
	}
	
	vvi dp(n+1, vi(n));
	rep(j, n)
		dp[1][j] = 0;
	
	reep(i, 2, n+1){
		rep(j, n-i+1){
			dp[i][j] = INF;
			reep(k, 1, i){
				int cost = cards[j].first * cards[j+k-1].second * cards[j+k].first * cards[j+i-1].second;
				dp[i][j] = min(dp[i][j], dp[k][j] + dp[i-k][j+k] + cost);
			}
		}
	}
	
	printf("%d\n", dp[n][0]);
	
	return 0;
}