// Steve J. Hodges
// CS19: C++ Programming Fall 2005
// 2dDynamicArray.cpp   two dimensional dynamic (run-time) array demo

#include <iostream>
using std::cout;
using std::cin;
using std::endl;

// a function with a (run-time sized) 2d array parameter
void print2dArray(int**, int, int);

main(){
  int simple[5][5]; // compile-time sized 2d arrays are simple
  simple[3][4] = 100;

  int **myArray;  // a run-time sized 2d has trickier initialization syntax
  int c, r; // number of columns and rows for our array

  cout << "CS19: Simple Two Dimensional Array Demo" << endl;
  cout << "Enter number of columns:"; cin >> c;
  cout << "Enter number of rows:"; cin >> r; cout << endl;

  // initialize a run-time sized two dimensional array
  myArray = new int*[r]; // create first dimension (of pointers to 2nd dimension)
  for (int i=0; i<r; i++){
    myArray[i] = new int[c]; // create second dimension(s) 
  }

  // assign test values
  for(int i=0; i<r; i++)
    for(int j=0; j<c; j++)
      myArray[i][j] = i*j;

  print2dArray(myArray, c, r);
}

// given a 2d array, print indecies and data in a table
void print2dArray(int **a , int x, int y){
  cout << "\t";
  for(int j=0; j<x; j++)
    cout << j << "\t";
  cout << endl << "\t";
  for(int j=0; j<x; j++)
    cout << "--------";
  cout << endl;
  for(int i=0; i<y; i++){
    cout << i << ":\t";
    for(int j=0; j<x; j++){
      cout << a[i][j] << "\t";
    }
    cout << endl;
  }
}