【数据结构基础】哈夫曼编码/译码课程设计

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define N 20
typedef struct {
char ch;
int weight;
int lchild, rchild, parent;
}Hufnode,*THufnode;
typedef struct{
char *code;
int length;
}CodeType;
//选择排序法 找1~n+i-1中parent不等于-1,且权值最小的两个结点,只选不排
void Select(THufnode T, int len, int *s1, int *s2) {
int i = 1, j, min1, min2;
while (i <= len) {//找到*s1
if (i <= len && T[i].parent == -1) {
min1 = i;
for (j = i; j <= len; j++) {
if (T[min1].weight >= T[j].weight && T[j].parent == -1) {
min1 = j;
}
}
*s1 = min1;
break;
}
else {
i++;
}
}
i = 1;
while (i <= len) {//找到*s2
if (i <= len && T[i].parent == -1 && i != min1) {
min2 = i;
for (j = i; j <= len; j++) {
if (T[min2].weight >= T[j].weight && T[j].parent == -1 && T[j].weight >T[*s1].weight) {
min2 = j;
}
}
*s2 = min2;
break;
}
else {
i++;
}
}
}
/*----------------Create hufmanTree-------------------------------*/
void Create_HufTree(THufnode *T, int n) {
*T=(THufnode)malloc(sizeof(Hufnode)*(2*n));
int i, m, sum;
int c,k,f,j;
char temp
;
m = n*2-1;
for (i = 1; i <= n; i++) {
printf("Please input the weight and node name in turn:");
scanf("%d %c",&((*T)[i].weight),&((*T)[i].ch));
(*T)[i].parent = -1;
(*T)[i].lchild = -1;
(*T)[i].rchild = -1;
}
for (i = n + 1; i <= m; i++) {
(*T)[i].ch=' ';
(*T)[i].weight = -1;
(*T)[i].lchild = -1;
(*T)[i].rchild = -1;
(*T)[i].parent = -1;
}
//初始化哈夫曼树
for (i = 1; i <= m; i++) {
printf("(*T)[%d].ch=%c\t (*T)[%d].weight=%d\t (*T)[%d].lchild=%d\t (*T)[%d].rchild=%d\n ", i,(*T)[i].ch,i, (*T)[i].weight, i, (*T)[i].lchild, i, (*T)[i].rchild);
}
//生成哈夫曼树
for (i = 1; i <= n - 1; i++) {
int s1, s2;
Select(*T, n + i - 1, &s1, &s2);
sum = (*T)[s1].weight + (*T)[s2].weight;
(*T)[s1].parent = n + i;
(*T)[s2].parent = n + i;
(*T)[n + i].lchild = s1;
(*T)[n + i].rchild = s2;
(*T)[n + i].weight = sum;
}
for (i = 1; i <= m; i++) {
printf("(*T)[%d].weight=%c\t (*T)[%d].weight=%d\t (*T)[%d].lchild=%d\t (*T)[%d].rchild=%d\t (*T)[%d].parent=%d\n",i, (*T)[i].ch, i, (*T)[i].weight, i, (*T)[i].lchild, i, (*T)[i].rchild, i, (*T)[i].parent);
}
}

/*--------------Hufman encoding-----------------------------*/
void HufTree_Encoding(THufnode *T,int n){
int i,j,c,k,f;
char temp[50];
CodeType cd[50];
for(i=1;i<=n;i++){
c=0;
cd[i].length=0;
for(k=i,f=(*T)[i].parent;f!=-1;k=f,f=(*T)[f].parent){
if((*T)[f].lchild==k){
temp[c]='0';
c++;
cd[i].length++;
}
else{
temp[c]='1';
c++;
cd[i].length++;
}
}
cd[i].code=(char*)malloc(c+1);
cd[i].code[c]='\0';
c--;
k=0;
while(c>=0){
cd[i].code[k++]=temp[c--];
}
}
for(i=1;i<=n;i++){
printf("%c: ",(*T)[i].ch);
for(j=0;j<cd[i].length;j++){
printf("%c",cd[i].code[j]);
}
printf("\n");
}
}
/*-----------------Hufman decoding-------------------------------*/
void HufTree_Decoding(THufnode *T,int n){
char code[50];
int i,len;
int f;
char temp[50];
printf("Please input message flow:");
scanf("%s",code);
len=strlen(code);
f=2*n-1;
for(i=0;i<=len;i++){
if((*T)[f].lchild!=-1 && (*T)[f].rchild!=-1){
if(code[i]=='0'){
f=(*T)[f].lchild;
}else{
if(code[i]=='1'){
f=(*T)[f].rchild;
}
}
}else{
printf("%c ",(*T)[f].ch);
i--;
f=2*n-1;
}
}
}

int main(void) {
THufnode T=NULL;
int len,i,option;
int w
;
CodeType cd[2*N];
while(1){
printf("\n\t\t****************hufman coding******************\n");
printf("\t\t*\t     1:Create HuffmanTree             *\n");
printf("\t\t*\t     2:Huffman Encoding               *\n");
printf("\t\t*\t     3:Huffman Decoding               *\n");
printf("\t\t*\t     0:exit                           *\n");
printf("\t\t***********************************************\n");
printf("\n请输入序号：");
scanf("%d", &option);
switch(option){
case 1:{
printf("Please input the number of nodes: ");
scanf("%d",&len);
Create_HufTree(&T,len);
break;
}
case 2:{
if(T==NULL){
printf("Before,You must create Huffman Tree");
break;
}
HufTree_Encoding(&T,len);
break;
}
case 3:{
HufTree_Decoding(&T,len);
break;
}
case 0:{
exit(0);
}
}
}
return 0;
}