#ifndef SORTER_H
#define SORTER_H
class sorter { 
   public: 
      sorter(int* intFile);  // Constructor  reads in the grid  from the infile 
//Precondition: gridFile must be a pointer to a string of characters naming an input file
//Postcondtion: The input file has been opened and contents stored in a newly // allocated array based on size from the file

	void mergeSort();
	void m_sort(int numbers[], int temp[], int left, int right);
	void merge(int numbers[], int temp[], int left, int mid, int right);
	void display();
      
   
   private: 
      int *intArr; 
      int size;
	  int *numbers;
	  int *tempArr;
       
};
#endif

//CECS 302 - CODY SLEDGE

#include "sorter.h"
#include <iostream>
#include <cstdlib>
#include <fstream>
#include <cassert>
using namespace std;

sorter::sorter(char *intFile)
{
	//Precondition: intFile must be a pointer to a string of characters naming an input file
	//Postcondtion: The input file has been opened and contents stored in a newly allocated array based
			     // on size from the file
                         
                            ifstream infile;
                            infile.open(intFile);
                            assert(infile);
                            
                            
                            infile >> size; //gets size of int array
                            
                            
                            //Allocate space for new array based on input from file
                            intArr = new int[size];
							nums = new int[size];
                            tempArr = new int[size];
                            
                            // Write data from file into new array
                            for(int i=0; i < size; i++)
                            {
                                    int val;
                                    infile >> val;
                                    intArr[i] = val;
                            }                           
                            
                            infile.close(); // Closes the opened file
                            return; // Constructor doens't return a value
}

void sorter::mergeSort()
{
  m_sort(this->intArr, this->tempArr, 0, this->size - 1);
}



void sorter::m_sort(int intArr[], int tempArr[], int left, int right)
{
  int mid;

  if (right > left)
  {
    mid = (right + left) / 2;
    m_sort(intArr, tempArr, left, mid);
    m_sort(intArr, tempArr, mid+1, right);

    merge(intArr, tempArr, left, mid+1, right);
  }
}


void sorter::merge(int intArr[], int tempArr[], int left, int mid, int right)
{
  int i, left_end, num_elements, tmp_pos;

  left_end = mid - 1;
  tmp_pos = left;
  num_elements = right - left + 1;

  while ((left <= left_end) && (mid <= right))
  {
    if (intArr[left] <= intArr[mid])
    {
      tempArr[tmp_pos] = intArr[left];
      tmp_pos = tmp_pos + 1;
      left = left +1;
    }
    else
    {
      tempArr[tmp_pos] = intArr[mid];
      tmp_pos = tmp_pos + 1;
      mid = mid + 1;
    }
  }

  while (left <= left_end)
  {
    tempArr[tmp_pos] = intArr[left];
    left = left + 1;
    tmp_pos = tmp_pos + 1;
  }
  while (mid <= right)
  {
    tempArr[tmp_pos] = intArr[mid];
    mid = mid + 1;
    tmp_pos = tmp_pos + 1;
  }

  for (i=0; i <= num_elements; i++)
  {
    intArr[right] = tempArr[right];
    right = right - 1;
  }
  

}

void sorter::display()
{
	for(int i=0; i< this->size; i++)
	{
		cout << intArr[i] << endl;
	}
}

//CECS 302 - CODY SLEDGE

#include "sorter.h"
#include <iostream>
#include <cstdlib>
#include <fstream>
#include <cassert>
using namespace std;

int main() { 
 sorter s("input.txt");
 s.mergeSort();
 cout<< endl;
 s.display();
 cout << endl;
 
 system("PAUSE");
}

      sorter(int* intFile);  // Constructor  reads in the grid  from the infile