This is another interview question, How do we convert a  binary tree to a heap ?

function visitNode(root, data) {
if (root)
{
data.push(root.val);
visitNode(root.left, data);
visitNode(root.right, data);
}
}

function heapify(data) {
if (data && data.length > 0)
{
int i = 0;
var root = {val: data[0], left : null, right: null};
var parent = null;
for (int i = 0; i <= data.length / 2; i++)
{
root.left = {val: data[2i+1], left : null, right: null};
root.right = {val: data[2i+2], left : null, right: null};
If (parent)
{
if ( i % 2 == 0) parent.right = root;
else parent.left = root;
}
parent = root;
root = {val: data, left : null, right: null};

}


}

data  = []
visitNode(root, data);
sort(data);
heapify(data);