Priority queue: Difference between revisions

=={{header|Arturo}}==

<syntaxhighlight lang="arturo">define :item [priority, value][

print: [

~"(|this\priority|, |this\value|)"

]

]

define :queue [items][

init: [

this\items: arrange this\items 'it -> it\priority

]

]

empty?: function [this :queue][

zero? this\items

]

push: function [this :queue, item][

this\items: this\items ++ item

this\items: arrange this\items 'it -> it\priority

]

pop: function [this :queue][

ensure -> not? empty? this

result: this\items\0

this\items: remove.index this\items 0

return result

]

Q: to :queue @[to [:item] [

[3 "Clear drains"]

[4 "Feed cat"]

[5 "Make tea"]

[1 "Solve RC tasks"]

]]

push Q to :item [2 "Tax return"]

print ["queue is empty?" empty? Q]

print ""

while [not? empty? Q]->

print ["task:" pop Q]

print ""

print ["queue is empty?" empty? Q]</syntaxhighlight>

{{out}}

<pre>queue is empty? false

task: (1, Solve RC tasks)

task: (2, Tax return)

task: (3, Clear drains)

task: (4, Feed cat)

task: (5, Make tea)

queue is empty? true</pre>