Does anyone have any idea why I would be getting a stack overflow on my quicksort in the following code?:

```
   private int[] concat( int[] less, int inxl, int pivot, int inxm, int[] more )
   {

      int[] concated = new int[ less.length ];

      for( int inx = 0; inx < inxl; inx++ )
      {

         concated[ inx ] = less[ inx ];

      }

      concated[ inxl ] = pivot;
      inxl++;

      for( int inx = 0; inx < inxm; inx++ )
      {

         concated[ inxl ] = more[ inx ];
         inxl++;

      }      

      return concated;

   }

   private int[] quickSort( int[] array )
   {

      if( array.length <= 1 )
         return array;

      int[] less = new int[ array.length ];
      int[] more = new int[ array.length ];
      int inxl = 0, inxm = 0;

      for( int inx = 1; inx < array.length; inx++ )
      {

         if( array[ inx ] < array[ 0 ] )
         {

            less[ inxl ] = array[ inx ];
            inxl++;

         }
         else
         {

            more[ inxm ] = array[ inx ];
            inxm++;

         }

      }

      return concat( quickSort( less ), inxl, array[ 0 ], inxm, quickSort( more ) );

   }

```

Any help would be greatly appreciated. I am revising for an interview and been a little rusty so time is of grave importance. Thanks upfront! :)

Sincerely,
Piotr.