Queues & Priority Queues - Beau teaches JavaScript
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Date: 2022-03-14
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Comments and reviews: 10
Bijay
The simple code along with the soft voice makes it so easy and quick to understand these things. Just a tip: You can put the collection with array of items on a side window or as comments beside the line of code that you are currently explaining so it's easy to see the code along with collection ( eg. the part where you do colletion[ i ] [1]). Not a big thing, but human brain's algorithm is bit slow in searching memory queues (pun intended), especially for beginners. Thank you Beau, you are AWESOME and please keep sharing. Have a nice day :)
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The simple code along with the soft voice makes it so easy and quick to understand these things. Just a tip: You can put the collection with array of items on a side window or as comments beside the line of code that you are currently explaining so it's easy to see the code along with collection ( eg. the part where you do colletion[ i ] [1]). Not a big thing, but human brain's algorithm is bit slow in searching memory queues (pun intended), especially for beginners. Thank you Beau, you are AWESOME and please keep sharing. Have a nice day :)
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Charlie
for this.enqueue function isn't line 41: if(this.isEmpty()) a bit redundant since we would just be doing the same thing in line 52? If collection is empty, then var added will remain false since the If-statement in the for-loop would never evaluate to true and therefore the element would be pushed onto collections.
Are we just checking for the empty array right away so in the case where the array is empty we could just stop the function early? Does this help performance or something?
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for this.enqueue function isn't line 41: if(this.isEmpty()) a bit redundant since we would just be doing the same thing in line 52? If collection is empty, then var added will remain false since the If-statement in the for-loop would never evaluate to true and therefore the element would be pushed onto collections.
Are we just checking for the empty array right away so in the case where the array is empty we could just stop the function early? Does this help performance or something?
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Tushar
Anyone please correct me if I am wrong, when we are running a loop to check for priorities... lets say this is the sample collections [ ['a', 4], ['b', 3], ['c', 2]] and I want to add ['d', 1]. If we run look from i = 0 to collection.length with if condition of element[1] < collection[i][1], we will end up with [ ['d', 1], ['a', 4], ['b', 3], ['c', 2]], but if we run with if condition of element[1] > collection[i][1], we will get [ ['a', 4], ['b', 3], ['c', 2], ['d', 1] ] ....
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Anyone please correct me if I am wrong, when we are running a loop to check for priorities... lets say this is the sample collections [ ['a', 4], ['b', 3], ['c', 2]] and I want to add ['d', 1]. If we run look from i = 0 to collection.length with if condition of element[1] < collection[i][1], we will end up with [ ['d', 1], ['a', 4], ['b', 3], ['c', 2]], but if we run with if condition of element[1] > collection[i][1], we will get [ ['a', 4], ['b', 3], ['c', 2], ['d', 1] ] ....
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Always remember to repent of your sins (sin is transgression of YAHUAH The Father In Heaven-s LAW: Genesis, Exodus, Leviticus, Numbers, & Deuteronomy) And Have Belief On Yahusha The Messiah. HE Died and Rose three days later so that you can be forgiven of your sins!
HE Loves you! Come to HIM------
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Jay
The enqueue function here is linear. If you use a heap as the storage, you will have logarithmic enqueue/dequeue functions. Using a heap, you can still maintain FIFO within a given priority level by performing a secondary comparison to an -epoch- or -addedAt- parameter.
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The enqueue function here is linear. If you use a heap as the storage, you will have logarithmic enqueue/dequeue functions. Using a heap, you can still maintain FIFO within a given priority level by performing a secondary comparison to an -epoch- or -addedAt- parameter.
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Acad-mie
I didn't get collection.splice(i, 0, element) in PriorityQueue.enqueue('cedar', 2)
Is not element[0] and not just element, because enqueue have 2 parameters in an array?
EDIT: I got it, bc he's adding the priority too...
Nice implementation
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I didn't get collection.splice(i, 0, element) in PriorityQueue.enqueue('cedar', 2)
Is not element[0] and not just element, because enqueue have 2 parameters in an array?
EDIT: I got it, bc he's adding the priority too...
Nice implementation
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Mohaiminul
Thanks. This helped me with my pathfinding visualizer. But during enqueue I compared current priority > iterated priority. I guess it has something to do with min-heap / max-heap. Once I made that change pathfinding was faster than DFS in my grid.
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Thanks. This helped me with my pathfinding visualizer. But during enqueue I compared current priority > iterated priority. I guess it has something to do with min-heap / max-heap. Once I made that change pathfinding was faster than DFS in my grid.
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israel
if you remove form the beginning of an array the complexity is O(n) if you remove from a linked list it is O(1). Does this mean that for coding interviews I have to implement my own linked list queue?
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if you remove form the beginning of an array the complexity is O(n) if you remove from a linked list it is O(1). Does this mean that for coding interviews I have to implement my own linked list queue?
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Jason
In the priority queue, why not use index as the priority? Then each index has a collection and just check if it's empty or not instead of looping through all the elements?
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In the priority queue, why not use index as the priority? Then each index has a collection and just check if it's empty or not instead of looping through all the elements?
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Shayn
How do I dynamically assign priority to data being sent into the array/collection array instead of it being hard-coded like how you have it in the video?
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How do I dynamically assign priority to data being sent into the array/collection array instead of it being hard-coded like how you have it in the video?
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