#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
#include <time.h>
 
#define MAX_ROWS 5000
#define MAX_COLUMNS 5000
 
struct array
{
        int rows;
        int columns;
        int order;
        char *base_pointer; /* pointer to array of bytes. In this array, float numbers will be stored (4 bytes each) */
};
struct array* initialize(int rows, int columns, int order)
{
  int i,
  	  size = columns * rows * sizeof(float);
  /* Allocate the required memory for the 2D array to store float values (Ex: 1.45) with "rows" and "columns" */
 
  // If you want to allocate both the structure and the internal storage in one malloc:
  /*
  struct array* array = (struct array*) malloc(sizeof(struct array) + size);
  array->base_pointer = &((char*)array)[sizeof(struct array)];
  */
 
  struct array* array = malloc(sizeof(struct array));
  if(!array) {
  	return 0; // error
  }
  array->base_pointer = malloc(size);
  if(!array->base_pointer) {
  	return 0; // error
  }
 
  for(i = 0; i < size; i++) {
  	array->base_pointer[i] = 0;
  }
  /* Make sure the size is within 1 to MAX_ROWS and 1 to MAX_COLUMNS specified in main.c. If not return null pointer */
  array->rows = rows;
  array->columns = columns;
  array->order = order;
  /* Initialize the 2D array to the all zeroes (0.0) */
  /* Assign suitable values to all the elements of the structure and return the struct pointer */
  return array;
 }
 
 void insert(struct array* arr, int row, int column, float value) {
 	float* floatArr = (float*)arr->base_pointer;
 	floatArr[(column * arr->rows) + row] = value;
 }
 
 float retrieve(struct array* arr, int row, int column) {
 	float* floatArr = (float*)arr->base_pointer;
 	return floatArr[(column * arr->rows) + row];
 }
 
 int main() {
 	struct array* arr = initialize(3, 4, 42);
 
 
 	int i, row, column;
 	float f = 0.0;
 	for(column = 0; column < arr->columns; column++) {
 		for(row = 0; row < arr->rows; row++) {
 			insert(arr, row, column, f);
 			f = f + 1.0;
 		}
 	}
 
 	// Check the array's fields
 	printf("arr->rows = %i\narr->columns = %i\narr->order = %i\n", arr->rows, arr->columns, arr->order);
 	// print the array linearly
 	for(i = 0; i < arr->columns*arr->rows; i++) {
 		printf("((float*)arr->base_pointer)[%i] = %f\n", i ,((float*)arr->base_pointer)[i]);
 	}
 
 
 	return 0;
 }

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