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Thread: Java selection sort

  1. #1
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    Default Java selection sort

    I'm currently doing selection sort and this is my method to sort a array of string into alphabet order. I interpret the code line by line into words and test it by hand it seem to make sense but when I run it, the array won't be in order. Can anyone help me find where I went wrong? Thanks
        public static void sortTitles(Movie3[]list )
        {   
                 //Movie3 [] dest = new Movie3[list.length];
                 Movie3 temp;
                 int max ;
                for(int x = list.length-1 ; x > 0 ;x--)
                    {
                    String next = list[x].getTitle();
                    max = x;
                    for(int i = 0 ; i < x ;i++)
                    {
     
                        if((next.compareTo(list[i].getTitle())) > 0 )
                        {
                            max =  i ;
                        }
     
                    }
                    temp = list[x];
                    list[x] = list[max];
                    list[max] = temp;
                }
     
        }


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    Default Re: Java selection sort

    What will be the value in max at the end of the inner loop?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Java selection sort

    Thanks for the hints on the value of max.
    Here is my new code and it working, but I don't understand why the inner loop need to have an index of max which = i for it to work.
        public static void sortTitles(Movie3[]list )
        {   
     
             Movie3 temp;
             int max ;
            for(int x = list.length-1 ; x > 0 ;x--)
            { 
             max = 0 ;
             for(int i = 1 ; i <= x ;i++)
             {
                 String next = list[max].getTitle();
                if((next.compareTo(list[i].getTitle())) > 0 )
                {
                 max =  i ;
                }
                System.out.println(max);
                    }
             temp = list[x];
             list[x] = list[max];
             list[max] = temp;
             }
         }

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