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pQueue

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+local function sift_up(queue, index)
+	local current, parent = index, (index - (index % 2))/2
+	while current > 1 and queue.cmp(queue[current][2], queue[parent][2]) do
+		queue[current], queue[parent] = queue[parent], queue[current]
+		current, parent = parent, (parent - (parent % 2))/2
+	end
+	return current
+end
+
+local function sift_down(queue, index)
+	local current, child, size = index, 2*index, #queue
+	while child <= size do
+		if child < size and queue.cmp(queue[child + 1][2], queue[child][2]) then
+			child = child + 1
+		end
+		if queue.cmp(queue[child][2], queue[current][2]) then
+			queue[current], queue[child] = queue[child], queue[current]
+			current, child = child, 2*child
+		else
+			break
+		end
+	end
+	return current
+end
+
+local methods = {
+
+	insert = function(self, element, value)
+		table.insert(self, {element, value})
+		return sift_up(self, #self)
+	end,
+
+	remove = function(self, element, compFunc)
+		local index = self:contains(element, compFunc)
+		if index then
+			local size = #self
+			self[index], self[size] = self[size], self[index]
+			local ret = table.remove(self)
+			if size > 1 and index < size then
+				sift_down(self, index)
+				if index > 1 then
+					sift_up(self, index)
+				end
+			end
+			return unpack(ret)
+		end
+	end,
+
+	pop = function(self)
+		if self[1] then
+			local size = #self
+			self[1], self[size] = self[size], self[1]
+			local ret = table.remove(self)
+			if size > 1 then
+				sift_down(self, 1)
+			end
+			return unpack(ret)
+		end
+	end,
+
+	peek = function(self)
+		if self[1] then
+			return self[1][1], self[1][2]
+		end
+	end,
+
+	contains = function(self, element, compFunc)
+		for index, entry in ipairs(self) do
+			if (compFunc and compFunc(entry[1], element)) or entry[1] == element then
+				return index
+			end
+		end
+		return false
+	end,
+
+	isEmpty = function(self)
+		return #self == 0
+	end,
+
+	size = function(self)
+		return #self
+	end,
+
+	getValue = function(self, element, compFunc)
+		local index = self:contains(element, compFunc)
+		return (index and self[index][2]) or false
+	end,
+
+	setValue = function(self, element, value, compFunc)
+		local index = self:contains(element, compFunc)
+		if index then
+			self[index][2] = value
+			sift_up(self, index)
+			sift_down(self, index)
+			return true
+		else
+			return false
+		end
+	end,
+
+}
+
+function new(compareFunc)
+	local queue = {}
+	queue.cmp = type(compareFunc) == "function" and compareFunc or function(a, b) return a < b end
+	setmetatable(queue, {__index = methods})
+	return queue
+end