Implementation of Huffman encoding c

Huffman encoding: Based on the Huffman tree, the data structure used is a binary tree.

Typedef int elemtype; typedef struct {elemtype weight; int parent, l_child, r_child;} binarytree; // 2. Construct the optimal binary tree void createhuffman (INT leafnum, binarytree * huffmantree) {// leafnum leaves, decide nodenum nodes int nodenum = 2 * leafnum-1; huffmantree = (binarytree *) malloc (nodenum * sizeof (binarytree )); // 0 unit also use // leafnum leaves, determine nodenum knot points, also decided (nodenum-1) bit encoding char * huffmancode; huffmancode = (char *) malloc (nodenum-1) * sizeof (CH AR); // initialization of the huffmantree: manually input the data weight of the leaf node. The default values of non-leaf nodes are 0 cout. <"Enter the leaf weight:"; int I; for (I = 0; I <nodenum; I ++) {if (I <leafnum) {CIN> huffmantree [I]. weight;} else {huffmantree [I]. weight = 0;} huffmantree [I]. parent = huffmantree [I]. rochelle child = huffmantree [I]. r_child = 0;} Int J; // J starting from leafnum, it refers to the node number that contains the new subtree for (j = leafnum; j <nodenum; j ++) {int W1 = 32767, W2 = 0; // minimum stored weight; int p = 0, q = 0; // Number of the minimum stored weight; int K; for (k = 0; k <j; k ++) {If (huffmantree [K ]. Parent = 0) // determine whether the node uses {If (huffmantree [K]. weight <W1) {W2 = W1; q = P; W1 = huffmantree [K]. weight; P = K;} else if (huffmantree [K]. weight <W2) {W2 = huffmantree [K]. weight; q = K ;}}// P corresponds to the left node, encoded as '0'; q corresponds to the left node, encoded as '1 '; huffmancode [p] = '0'; huffmancode [Q] = '1'; huffmantree [J]. weight = W1 + W2; huffmantree [J]. rochelle child = P; huffmantree [J]. r_child = Q; huffmantree [p]. parent = J; huffmantree [Q]. parent = J;} // 3. Search for the code huffmancodin from the subnode to the root node. G (int n, binarytree * huffmantree) // For each leaf, search for huffmancode from the leaf to the root. // For each leaf, the corresponding encoding length is codelengthconst int maxsize = 10; char iscode [maxsize] [maxsize]; int m; For (m = 0; m <leafnum; m ++) // start from the first leaf and find {int n = 0; iscode [m] [N] = huffmancode [m]; int parent = huffmantree [M]. parent; while (parent! = 0) {iscode [m] [++ N] = huffmancode [Parent]; parent = huffmantree [Parent]. parent;}; int X; cout <"no." <m + 1 <"leaf huffmancode ----"; for (x = 0; x <N; X ++) cout <iscode [m] [X]; cout <Endl ;}} void main () {binarytree * T = 0; int leafnum; printf ("Number of input leaves n = \ n"); CIN> leafnum; createhuffman (leafnum, T); While (1 );}

The compilation result is as follows: