Editing Binary heap (section)

=== Decrease or increase key ===
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The decrease key operation replaces the value of a node with a given value with a lower value, and the increase key operation does the same but with a higher value. This involves finding the node with the given value, changing the value, and then down-heapifying or up-heapifying to restore the heap property.

Decrease key can be done as follows:

# Find the index of the element we want to modify
# Decrease the value of the node
# Down-heapify (assuming a max heap) to restore the heap property

Increase key can be done as follows:

# Find the index of the element we want to modify
# Increase the value of the node
# Up-heapify (assuming a max heap) to restore the heap property