```/*************************************************
** This program reads in points from the user and
** prints them back out in sorted order from
** closest to the origin to farthest.
*************************************************/
#include <iostream>
using namespace std;

/*************************************************
** PROTOTYPES
*************************************************/
void selectionsort(double **A, int N);

/*************************************************
** MAIN
*************************************************/
int main()
{
// Get number of points and create & read array
int n;
cout << "How many points? ";
cin >> n;
cout << "Enter points (x,y,z): ";
double **A = new double*[n];
for(int i = 0; i < n; i++)
{
A[i] = new double[3];
char c;
cin >> c >> A[i][0]
>> c >> A[i][1]
>> c >> A[i][2] >> c;
}

// Sort points!
selectionsort(A,n);

// Print out points
for(int i = 0; i < n; i++)
{
cout << '(' << A[i][0]
<< ',' << A[i][1]
<< ',' << A[i][2] << ") ";
}
cout << endl;
return 0;
}

/*************************************************
** DEFINITIONS
*************************************************/
bool before(double *a, double *b)
{
return sqrt(a[0]*a[0] + a[1]*a[1] + a[2]*a[2])
<
sqrt(b[0]*b[0] + b[1]*b[1] + b[2]*b[2]);
}

void selectionsort(double **A, int N)
{
for(int length = N; length > 1; length--)
{
// Find imax, the index of the largest
int imax = 0, i;
for(i = 1; i < length; i++)
if (before(A[imax],A[i]))
imax = i;
// Swap A[imax] & the last element
double *temp = A[imax];
A[imax] = A[length - 1];
A[length - 1] = temp;
}
}

```