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 class below:
class MinHeap {
constructor() {
this.storage = [];
this.size = 0;
}
getLeftChildIndex(index) {
return 2 * index + 1;
}
getRightChildIndex(index) {
return 2 * index + 2;
}
// check if this rounds down
getParentIndex(index) {
return Math.floor((index - 1) / 2)
}
hasLeftChild(index) {
return this.getLeftChildIndex(index) < this.size;
}
hasRightChild(index) {
return this.getRightChildIndex(index) < this.size;
}
hasParent(index) {
return this.getParentIndex(index) >= 0;
}
leftChild(index) {
return this.storage[this.getLeftChildIndex(index)];
}
rightChild(index) {
return this.storage[this.getRightChildIndex(index)];
}
parent(index) {
return this.storage[this.getParentIndex(index)];
}
isFull() {
return this.size == this.capacity;
}
swap(index1, index2) {
let temp = this.storage[index1];
this.storage[index1] = this.storage[index2];
this.storage[index2] = temp;
}
insert(data) {
this.storage[this.size] = data;
this.size += 1;
this.heapifyUp();
}
heapifyUp() {
let index = this.size - 1;
while (this.hasParent(index) &&
this.parent(index) > this.storage[index]) {
this.swap(this.getParentIndex(index), index);
index = this.getParentIndex(index);
}
}
removeMin() {
// if (this.size == 0)
// throw new Error("Empty Heap");
let data = this.storage[0];
this.storage[0] = this.storage[this.size - 1];
this.size -= 1;
this.heapifyDown();
return data;
}
heapifyDown() {
let index = 0;
while (this.hasLeftChild(index)) {
let smallerChildIndex = this.getLeftChildIndex(index);
if (this.hasRightChild(index) && this.rightChild(index) < this.leftChild(index))
smallerChildIndex = this.getRightChildIndex(index);
if (this.storage[index] < this.storage[smallerChildIndex])
break;
else
this.swap(index, smallerChildIndex);
index = smallerChildIndex;
}
}
getTop() {
return this.storage[0];
}
}
Could anyone please suggest changes to the above class to store and retrieve pairs.
Thanks
