[Tutor] remove function

[Kent Johnson]

Christopher Spears wrote:
> My apologies to everyone.  Here is the complete code:
>
>
> class PriorityQueue:
> 	def __init__(self):
> 		self.items = []
> 		
> 	def isEmpty(self):
> 		return self.items == []
> 		
> 	def insert(self, item):
> 		self.items.append(item)
> 		
> 	def remove(self):
> 		maxi = 0
> 		for i in range(1, len(self.items)):
> 			if self.items[i] > self.items[maxi]:
> 				maxi = i
> 		item = self.items[maxi]
> 		self.items[maxi:maxi+1] = []
> 		return item
>   
Slice indexing in Python is up-to-but-not-including. So

  self.items[maxi:maxi+1] = []

means, replace the slice of self.items, that starts at maxi and goes up 
to but not including maxi+1, with the empty list. So it is effectively 
deleting self.items[maxi], which could also be written as
  del self.items[maxi]

or combine it with the line above as
  item = self.items.pop(maxi)

By the way if this class is for production use, rather than learning, 
you should look into the heapq module, it implements a much more 
efficient algorithm than the one above. heapq implements a min heap, not 
a max heap, so you need some kind of wrapper for your items to get them 
in the order you want.

Kent