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Quick sort (Ascending Order)

candyfreak (9)
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void database::quickSortInt(int top,int bottom, char order)
{
      // top = subscript of beginning of array
      // bottom = subscript of end of array
     int middle;

     if (top < bottom)
     {
          middle = partitionInt(top, bottom,order);
          quickSortInt(top,middle,order);   // sort first section
          quickSortInt(middle+1,bottom,order);    // sort second section
     }
     return;
}

int database::partitionInt(int top, int bottom, char order)
{
     int x = indexField[top];
     int i = top - 1;
     int j = bottom + 1;
     int temp;

     if(order == 'd' || order == 'D')
     {
     do
     {
         do      
         {
	      j--;
         }while (x >indexField[j]);

         do  
         {
	      i++;
         }while (x <indexField[i]);

         if (i < j)
         { 
	     temp = indexField[i];    
             indexField[i] = indexField[j];
             indexField[j] = temp;

	     temp = primaryKey[i];
	     primaryKey[i] = primaryKey[j];
	     primaryKey[j] = temp;
         }

    }while (i < j);     
    return j;           // returns middle subscript  
    }
}


I got my Quick Sorting algorithm working but I'm having problems recreating it in ascending order. If anyone could offer any suggestions it would be much appreciated.
candyfreak (9)
I got it to go into descending order but for some reason its returning some random negative huge number. Ex. -3945934 and I'm missing my last index value.

I figure it's because my array is off by one to the left and it's accessing outside the array boundaries however i can't seem to figure out why it is doing so.

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void database::quickSortInt(int top,int bottom, char order)
{
      // top = subscript of beginning of array
      // bottom = subscript of end of array
     int middle;

     if (top < bottom)
     {
          middle = partitionInt(top, bottom,order);
          quickSortInt(top,middle,order);   // sort first section
          quickSortInt(middle+1,bottom,order);    // sort second section
     }
     return;
}

int database::partitionInt(int top, int bottom, char order)
{
     int x = indexField[top];
     int i = top - 1;
     int j = bottom + 1;
     int temp;

     if(order == 'd' || order == 'D')
     {
     do
     {
         do      
         {
	      j--;
         }while (x <indexField[j]); //just had to reverse

         do  
         {
	      i++;
         }while (x >indexField[i]); // just had to reverse

         if (i < j)
         { 
	     temp = indexField[i];    
             indexField[i] = indexField[j];
             indexField[j] = temp;

	     temp = primaryKey[i];
	     primaryKey[i] = primaryKey[j];
	     primaryKey[j] = temp;
         }

    }while (i < j);     
    return j;           // returns middle subscript  
    }
}


I believe i fixed it my J= was storing something outside of the array because of the bottom+1. I removed it and it fixed as far as i can tell for now. If anyone thinks their is something else wrong just let me know but for now its off to bed.
Last edited on
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