import std.algorithm;
import std.array;
import std.ascii;
import std.bigint;
import std.complex;
import std.container;
import std.conv;
import std.functional;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

auto readInts() {
	return array(map!(to!int)(readln().strip().split()));
}
auto readInt() {
	return readInts()[0];
}
auto readLongs() {
	return array(map!(to!long)(readln().strip().split()));
}
auto readLong() {
	return readLongs()[0];
}

void readlnTo(T...)(ref T t) {
    auto s = readln().split();
    assert(s.length == t.length);
    foreach(ref ti; t) {
        ti = s[0].to!(typeof(ti));
        s = s[1..$];
    }
}

const real eps = 1e-10;

void main(){
    auto n = readInt();
    long[] a, b;
    foreach(i; iota(n)) {
        auto ab = readInts();
        a ~= ab[0];
        b ~= ab[1];
    }
    long calc(uint i, uint j) {
        if(j == i+1) {
            return 0;
        }
        auto ans = long.max/2;
        foreach(k; iota(i+1, j)) {
            ans = min(
                    ans,
                    memoize!calc(i, k) + memoize!calc(k, j)
                    + a[i]*b[k-1]*a[k]*b[j-1]
                    );
        }
        return ans;
    }
    writeln(calc(0, n));
}