Please clear my doubt in this vide

we are deleting the node first replace the node value by infinity and then upheapify the in finity to root which is taking long(n) time if we directly swap the value with with root then no need to up heapyify please clear my doubt … and after that we will downheapify the root.

your approach is also correct but in that case u need to apply upheapify and down heapify both.