Question

Heap – Sort Algorithm
The problem I am having is this, this algorithms n input is 2, this is designed so that the 1st position (int i) of the array and the 2nd position (int j) have their values compared.

The problem is that this ignores the 0 position of the given array list. I have tried reducing certain values, this will create infinite loops. The algorithm is an adaptation of pseudocode. It isn’t designed to run arraylist from 0. I can’t think of how to re-adapt this algorithm into a decent minimum heap sort.

public static void input( ArrayList<input> vertexList, int n )
{
    int j=n; 
    int i=n/2; 
    input object = vertexList.get(n);

    while ((i>0) && vertexList.get(i)> object){

        vertexList.set(j, vertexList.get(i));

        j = i;
        i = i/2;
    }

    vertexList.set(j, object);

}

Answer 1

try to use vertexList.get(i-1) and vertexList.get(j-1) and vertexList.set(j-1, ...)