#include <fstream>
#include <iomanip>

using namespace std;

unsigned int N;
unsigned int x[100001], y[100001];

unsigned int xMin, xMax, yMin, yMax;
unsigned int LEFT, RIGHT, UP, DOWN;
unsigned int cnt1, cnt2;
unsigned int i, j, k, l, m;

double sol;

int main ()
{
    ifstream fin ("rubarba.in");
    fin >> N;
    for (i=1; i<=N; i++)
        fin >> x[i] >> y[i];
    fin.close();
    xMax = x[1];
    for (i=2; i<=N; i++)
        if (x[i] > xMax)
            xMax = x[i];
    xMin = x[1];
    for (i=2; i<=N; i++)
        if (x[i] < xMin)
            xMin = x[i];
    yMax = y[1];
    for (i=2; i<=N; i++)
        if (y[i] > yMax)
            yMax = y[i];
    yMin = y[1];
    for (i=2; i<=N; i++)
        if (y[i] < yMin)
            yMin = y[i];
    sol = (yMax-yMin) * (xMax-xMin);

    /*
    for (i=1; i<=N; i++)
        for (j=1; j<=N; j++)
            for (k=1; k<=N; k++)
                for (l=1; l<=N; l++)
                {
                    LEFT = x[i];
                    RIGHT = x[j];
                    UP = y[k];
                    DOWN = y[l];
                    for (m=1; m<=N; m++)
                        if (x[m] >= LEFT && x[m] <= RIGHT)
                            cnt1+;
                    for (m=1; m<=N; m++)
                        if (y[m] >= DOWN && y[m] <= UP)
                            cnt2++;
                }
    */
    ofstream fout ("rubarba.out");
    fout << fixed << setprecision(2) << sol;
    fout.close();
    return 0;
}