10b - TreesSlides

# Assume the following data items for an integer data

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Unformatted text preview: tree is already a heap. void MakeHeap(int node) { int curr, child, temp; curr = node; if (node <= nlast) // if there's a child { child = 2*node+1; if (value[node] < value[child]) node = child; child++; // is there a right child? if (child < n && value[node] < value[child]) node = child; } (node is now the element containing the largest of the values in the node and its children.) 19 if (node != curr) // not a heap { temp = value[node]; value[node] = value[curr]; value[curr] = temp; MakeHeap(node); } We can ensure that the subtrees are all heaps by checking them, starting from the bottom. Of course the last subtree is from node nlast. nlast } So the following code will do the whole task. Note the recursion to check the subtree now that its root has been altered. But wait, there's more. for (node=nlast;node>=0;node--) (node=nlast;node>=0;node--) MakeHeap(node); Here's our previous example. We exchange the first and last values. Since this procedure puts the largest at the root, we can use it to sort the data. 8 It's called Heapsort. It...
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