Question

My algorithm is not working, I’m a newbie to all algorithms and javascript and I just can’t seem to work out why it’s not working.

Here’s the Array (23, 19, 35, 12, 30)

Max value = 0

Here’s what I have…

For K= 0 to n – 2 

  MAX = 0

      For j = 0 to n – k - 2

                         If item[j] > item[MAX]
                         MAX = item[j] 

                  end if
          end for 
      swap n - k - 2 with item[MAX] 
   end for
end SelectionSort

Where have I gone wrong? thanks!!!!

Also, if anyone could tell me how to use it in a trace table I would be sooo happy!

Kind regards
Craig

Answer 1

Using max in this expression is causing the problem item[MAX], It would be j. Please give it a consideration and then try again like this, The selection sort Demo

     var arr = new Array (23, 19, 35, 12, 30);         
     temp = 0;

     for( k = 0; k < arr.length-1; k++)
     {

        for( j = k+1;  j < arr.length; j++)
        {

            if (arr [k] > arr [j])
            {

                 temp = arr[k];
                 arr[k] = arr[j];
                 arr[j] = temp;
            }
         }
     }

for(k = 0; k < arr.length; k++)
    alert(arr[k]);​