Describe every single line of this code(also describe output) for Viva

Huffman code;

#include #include #include #include

// This constant can be avoided by explicitly // calculating height of Huffman Tree #define MAX_TREE_HT 100

// A Huffman tree node struct MinHeapNode {

// One of the input characters char data;

// Frequency of the character unsigned freq;

// Left and right child of this node struct MinHeapNode *left, *right; };

// A Min Heap: Collection of // min-heap (or Huffman tree) nodes struct MinHeap {

// Current size of min heap unsigned size;

// capacity of min heap unsigned capacity;

// Array of minheap node pointers struct MinHeapNode** array; };

// A utility function allocate a new // min heap node with given character // and frequency of the character struct MinHeapNode* newNode(char data, unsigned freq) { struct MinHeapNode* temp = (struct MinHeapNode*)malloc (sizeof(struct MinHeapNode));

temp->left = temp->right = NULL; temp->data = data; temp->freq = freq;

return temp; }

// A utility function to create // a min heap of given capacity struct MinHeap* createMinHeap(unsigned capacity)

{

struct MinHeap* minHeap = (struct MinHeap*)malloc(sizeof(struct MinHeap));

// current size is 0 minHeap->size = 0;

minHeap->capacity = capacity;

minHeap->array = (struct MinHeapNode**)malloc(minHeap-> capacity * sizeof(struct MinHeapNode*)); return minHeap; }

// A utility function to // swap two min heap nodes void swapMinHeapNode(struct MinHeapNode** a, struct MinHeapNode** b)

{

struct MinHeapNode* t = *a; *a = *b; *b = t; }

// The standard minHeapify function. void minHeapify(struct MinHeap* minHeap, int idx)

{

int smallest = idx; int left = 2 * idx + 1; int right = 2 * idx + 2;

if (left < minHeap->size && minHeap->array[left]-> freq < minHeap->array[smallest]->freq) smallest = left;

if (right < minHeap->size && minHeap->array[right]-> freq < minHeap->array[smallest]->freq) smallest = right;

if (smallest != idx) { swapMinHeapNode(&minHeap->array[smallest], &minHeap->array[idx]); minHeapify(minHeap, smallest); } }

// A utility function to check // if size of heap is 1 or not int isSizeOne(struct MinHeap* minHeap) {

return (minHeap->size == 1); }

// A standard function to extract // minimum value node from heap struct MinHeapNode* extractMin(struct MinHeap* minHeap)

{

struct MinHeapNode* temp = minHeap->array[0]; minHeap->array[0] = minHeap->array[minHeap->size - 1];

--minHeap->size; minHeapify(minHeap, 0);

return temp; }

// A utility function to insert // a new node to Min Heap void insertMinHeap(struct MinHeap* minHeap, struct MinHeapNode* minHeapNode)

{

++minHeap->size; int i = minHeap->size - 1;

while (i && minHeapNode->freq < minHeap->array[(i - 1) / 2]->freq) {

minHeap->array[i] = minHeap->array[(i - 1) / 2]; i = (i - 1) / 2; }

minHeap->array[i] = minHeapNode; }

// A standard function to build min heap void buildMinHeap(struct MinHeap* minHeap)

{

int n = minHeap->size - 1; int i;

for (i = (n - 1) / 2; i >= 0; --i) minHeapify(minHeap, i); }

// A utility function to print an array of size n void printArr(int arr[], int n) { int i; for (i = 0; i < n; ++i) cout<< arr[i];

cout<<" "; }

// Utility function to check if this node is leaf int isLeaf(struct MinHeapNode* root)

{

return !(root->left) && !(root->right); }

// Creates a min heap of capacity // equal to size and inserts all character of // data[] in min heap. Initially size of // min heap is equal to capacity struct MinHeap* createAndBuildMinHeap(char data[], int freq[], int size)

{

struct MinHeap* minHeap = createMinHeap(size);

for (int i = 0; i < size; ++i) minHeap->array[i] = newNode(data[i], freq[i]);

minHeap->size = size; buildMinHeap(minHeap);

return minHeap; }

// The main function that builds Huffman tree struct MinHeapNode* buildHuffmanTree(char data[], int freq[], int size)

{ struct MinHeapNode *left, *right, *top;

// Step 1: Create a min heap of capacity // equal to size. Initially, there are // modes equal to size. struct MinHeap* minHeap = createAndBuildMinHeap(data, freq, size);

// Iterate while size of heap doesn't become 1 while (!isSizeOne(minHeap)) {

// Step 2: Extract the two minimum // freq items from min heap left = extractMin(minHeap); right = extractMin(minHeap);

// Step 3: Create a new internal // node with frequency equal to the // sum of the two nodes frequencies. // Make the two extracted node as // left and right children of this new node. // Add this node to the min heap // '$' is a special value for internal nodes, not used top = newNode('$', left->freq + right->freq);

top->left = left; top->right = right;

insertMinHeap(minHeap, top); }

// Step 4: The remaining node is the // root node and the tree is complete. return extractMin(minHeap); }

// Prints huffman codes from the root of Huffman Tree. // It uses arr[] to store codes void printCodes(struct MinHeapNode* root, int arr[], int top)

{

// Assign 0 to left edge and recur if (root->left) {

arr[top] = 0; printCodes(root->left, arr, top + 1); }

// Assign 1 to right edge and recur if (root->right) {

arr[top] = 1; printCodes(root->right, arr, top + 1); }

// If this is a leaf node, then // it contains one of the input // characters, print the character // and its code from arr[] if (isLeaf(root)) {

cout<< root->data <<": "; printArr(arr, top); } }

// The main function that builds a // Huffman Tree and print codes by traversing // the built Huffman Tree void HuffmanCodes(char data[], int freq[], int size)

{ // Construct Huffman Tree struct MinHeapNode* root = buildHuffmanTree(data, freq, size);

// Print Huffman codes using // the Huffman tree built above int arr[MAX_TREE_HT], top = 0;

printCodes(root, arr, top); }

// Driver code int main() {

char arr[] = { 'a', 'b', 'c', 'd', 'e','f'}; int freq[] = { 5, 9, 12, 13, 16, 45 };

int size = sizeof(arr)/sizeof (arr[0]);

HuffmanCodes(arr, freq, size);

getchar (); }