Questions tagged [min-heap]
181 questions
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How can i fix my implementation a generic Decrease-Key method in a Min Heap in java?
I want to decrease the value of an element with index i in my Min Heap data structure that i am implementing using an ArrayList (and then move the element in the correct position), here is the implementation of it, i will skip the insert, heapSize,…
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What is the meaning of vector*>?
I was solving a question on merging k sorted linked lists and I came across this vector*>:
Node* mergeKLists(vector*> &listArray);
I want to know if it is a declaration of all the linked lists, if it is how it has been…
cosmoabhi
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Why it resulting a "list index out of range error" on this dijkstra algorithm
I tried to implement a dijkstra algorithm on my own graph but it doesn't run instead it says that "list index out of range"
here is the code that i tried
it works on a smaller graph like with 6 nodes but mine has 39 nodes and the maker of this code…
Samuel
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priority queue question. priority is undefined in while loop. how to enqueue element to queue?
doing a priority queue as a min-heap in javascript. console keeps returning priority is undefined in the while loop. what is the problem? / how to enqueue element to queue?
//min-heap
class PriorityQueue {
constructor(){
this.values = [];
…
AlmostThere
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Heap Dijkstra Implementation is slower than Naive Dijsktra Implementation
I have tried to implement the Naive and Heap Dijkstra as shown below but somehow my naive Dijkstra implementation is surprisingly faster. I debugged my code but couldn't understand where my problem in my implementations are.
Why is my heap-based…
Jonsi Billups
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javascript min heap implementation for a storing a pair/tuple
I created a class to implement a min heap following a tutorial. It works fine for storing and retrieving integers. I want to store pairs in this class for example:
(5, 1)
(2, 4)
(6, 2)
The removeMin method should give (2, 4) back. Please find the…
Ashy Ashcsi
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Why Dijkstra worst time complexity is worse using priority queue compared without using it?
I know the sequence of step of Dijkstra algorithm is like these:
Initialize arr min_distance, put source as 0, and the others as MAX_VALUE
Pick the min distance that's not in visited set
Put vertex to the visited set
Loop through all edges linked…
ktvktv
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Inserting a node in a min-heap with a null value at the end
I got a sorted min-heap array: 2,3,4,5,NULL
I'd like to insert the value 1 in it, how would the first step be dealt with?
2 2
/ \ / \
3 4 or this? 3 4
/ \ / / \ …
student
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Why is this minHeap implementation incorrect?
I am using a PriorityQueue to solve the Meeting Rooms II problem from Leetcode. I have developed my own solution that fails on certain test cases, yet from my eyes it is indistinguishable from the provided solution, yet that solution passes all…
calvinhobbes123
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Which data structure is more efficient for A*?
In A* search, which data structure would be more efficient ? Min-heap or Binary search tree.
Considering that below operations are to be handled frequently:
(a) extract min
(b) search a node
(c) update the node
(d) insert a node
Note: Search…
aks
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What is wrong with my insert function for min-heaps?
I'm trying to write a minimum heap data structure in C, but I ran into some issues while implementing the insert function.
It looks like this :
void insert(MinHeap* minh , int key)
{
if(minh->itemcount == minh->maxSize)
{
…
blake
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What are the boundaries on increasing keys in minimum heap
I was asked this question on a test and would like to make sure I answered correctly:
You are given a min heap. We want to increase all the nodes on the left most path (so the root, node 2, node 4, node 8......) by a value of c, so that the heap…
Yair
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Maximum Number of comparison in a min heap to Determine Maximum number
A min-heap consist of 2047 elements, the maximum number of comparisons required to determine the maximum number of elements is _.
For this i went with approach as this is a min heap and the min element will be there in the root node. So to find the…
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In C++, when adding onto a minHeap, which calls the bubbleUp function, how can I lexicographically compare two things that have the same priority?
In C++, when adding onto a minHeap, which calls the bubbleUp function, how can I lexicographically compare two things that have the same priority?
I want the value that is smaller when compared lexicographically to come first in the heap. What…
coderlegend
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Merging two binary min-heaps
I have two binary min-heaps, where each one stores different keys. The trees are also complete binary trees. I want to merge these two into one binary min-heap of size exactly 2n. Preferably in O(long) time and O(1) space.
bennietgek
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