Questions tagged [max-heap]
148 questions
0
votes
0 answers
Writing Pseudocode to find smallest element in an array. [verification]
I need a solution verification. I could not find the tag so if anyone could assist me on that. Question is below.
Let A [1..n] be a max-heap with n elements. Assuming there are no duplicate keys.
Write pseudocode for finding the smallest element…
GiBiT
- 311
- 1
- 8
- 20
0
votes
1 answer
Insert into heap in at most one swap?
There's this question in the famous book "Introduction to Algorithms" by Udi Manber, which states that
Algorithm *Insert_To_Heap* may swap many times up the heap. Modify the algorithm so that at most one swap will be performed. O(log n)…
Arkanath Pathak
- 42
- 1
- 8
0
votes
1 answer
Insertions into a max heap with atmost one swap
Is there a algorithm to perform insertions into a heap with atmost one swap (O(log n) comparisons are allowed)
Jay
- 1
- 1
0
votes
1 answer
Heap, trickle down method
I am currently doing a max-heap. When I use remove() method, I understand that I would swap with the larger children. What if both of the children have the same priority? for instance
Case 1:
heap = [5,7,7,16,15]
if I remove 5 and replace it with…
Sugihara
- 1,091
- 2
- 20
- 35
0
votes
1 answer
Is this a valid MaxHeap structure?
I am trying to convert a minHeap class to a maxHeap class. I was given the code for the minHeap class, one method of which was add. It looks like this:
while (index > 1 && getParent(index).compareTo(newElement) > 0)
The first node is automatically…
Andrew Martin
- 5,619
- 10
- 54
- 92
0
votes
1 answer
How can I lower the cost of Heapsorts' Maxheap function from 2lg(n) to ~lg(n)? (Java)
Here is the heapsort program so far.
public class HeapSort{
private static int[] a;
private static int n;
private static int left_child;
private static int right_child;
private static int largest;
public static void main(String[] args) {
…
JessieM
- 11
- 3
-1
votes
1 answer
Why does my recursive code result in a stack overflow error?
This code is given in the book "Introduction to Algorithms". For this I used 1 indexed array
#include
#include
using namespace std;
int n=6;
int x[1000];
void max_heapify(int a[],int i)
{
int left=2*i;
int…
user466534
-1
votes
1 answer
what are the inputs given to the lambda expression(a,b) while creating a max priority queue in java
Started learning dsa and came across priority queues but I am stuck at lambda expressions in priority queue in java.
Map map = new HashMap<>();
PriorityQueue q = new PriorityQueue<>((a,b)->map.get(b)-map.get(a));
In the…
Namash Sharma
- 1
- 1
-1
votes
1 answer
Is finding the min/max of BST considered to be O(1) time?
I was building a queue using a BST, but I realized that a min/max heap might be better.
However, a BST might work, since if we store a reference to head/tail in the BST, then lookup is very close to O(1)..for example:
(5)
/ \
…
Alexander Mills
- 90,741
- 139
- 482
- 817
-1
votes
1 answer
Heapify method is not working properly for max heap
I am preparing for a data structures and algorithms final exam. I am trying to work through all of the data structures we have learnt this semester and program them by my self to help prepare me for the final. I am working on the max heap right now…
osty2001
- 1
- 2
-1
votes
1 answer
how to implement string priority queue with checking message priority
Messenger is used to send or receive text
messages. When someone is offline a messenger
maintains a buffer of messages which is delivered
to the receiver when he gets online.
The phenomena take place on simple
timestamp phenomena, the message…
-1
votes
1 answer
Is golang container/heap effectively doing heap sort?
Is golang container/heap effectively doing heap sort on an underlying slice?
It doesn't look like underlying array is always sorted.
type IntHeap []int
// ... other interface implementation
func main() {
a := []int{}
h := IntHeap(a)
…
Steve
- 863
- 3
- 9
- 21
-1
votes
1 answer
Max Heap Insert Function Implementation C++
I'm trying to insert key values into heap. I'm using TestUnit.cpp for errors. I got these errors:
Assert…
NOBUD
- 27
- 7
-1
votes
1 answer
Maxheap giving wrong result
I wrote the following code to build a maxheap from a already existing array the downadjust function makes the array a max heap but it is not producing results as desired
Please check the code and tell me where am I going wrong also it would be very…
user16393473
-1
votes
1 answer
max_heapify iterative way to go down the heaps to get the next level nodes
I am trying to write a iterative control loop instead of recursion because it is more efficient can someone tell me if my code makes sense:
Recursive version:
def max_heapify(array, i):
left = 2 * i
right = 2 * i + 1
length = len(array) - 1 # for…
Poala
- 5
- 2