写在前面
本篇实验代码非本人写，代码源自外部，经调试解决了部分warning和error后在本地vs上可以正常运行，如有运行失败可换至vs
未来会重构实现该两个实验
哈夫曼树及哈夫曼编码的算法实现
实验内容
内容要求：
1、初始化(Init)：能够对输入的任意长度的字符串s进行统计，统计每个字符的频度，并建立哈夫曼树
2、建立编码表(CreateTable)：利用已经建好的哈夫曼树进行编码，并将每个字符的编码输出。
3、编码(Encoding)：根据编码表对输入的字符串进行编码，并将编码后的字符串输出。
4、译码(Decoding)：利用已经建好的哈夫曼树对编码后的字符串进行译码，并输出译码结果。
测试数据：
输入字符串“thisprogramismyfavourite”，完成这28个字符的编码和译码。
代码实现
#include<iostream>
#include<string.h>
#include<queue>
#define MAX 10000
using namespace std;
char a[100], buff[1024], p;
typedef struct
{
char letter, * code;
int weight;
int parent, lchild, rchild;
}HTNode, * HuffmanTree;
int n;
char coding[100];
int Min(HuffmanTree& HT, int i)
{
int j;
int k = MAX;
int flag=0;
for (j = 0; j <= i; ++j)
{
if (HT[j].weight < k && HT[j].parent == 0)
{
k = HT[j].weight;
flag = j;
}
}
HT[flag].parent = 1;
return flag;
}
void Select(HuffmanTree& HT, int i, int& s1, int& s2)
{
s1 = Min(HT, i);
s2 = Min(HT, i);
}
void CreateHuffmanTree(HuffmanTree& HT, char t[], int w[])
{
int m;
int i, s1, s2;
if (n <= 1)
return;
m = 2 * n - 1;
HT = new HTNode[m + 1];
for (i = 0; i < n; i++)
{
char arr[] = "0";
char* pa = arr;
HT[i].code = pa;
HT[i].parent = 0;
HT[i].lchild = -1;
HT[i].rchild = -1;
HT[i].letter = t[i];
HT[i].weight = w[i];
}
for (i = n; i <= m; i++)
{
char arr[] = "0";
char* pa = arr;
HT[i].code = pa;
HT[i].parent = 0;
HT[i].lchild = -1;
HT[i].rchild = -1;
HT[i].letter = ' ';
HT[i].weight = 0;
}
cout << "********************************" << endl;
for (i = n; i < m; i++)
{
Select(HT, i - 1, s1, s2);
HT[s1].parent = i;
HT[s2].parent = i;
HT[i].lchild = s1;
HT[i].rchild = s2;
HT[i].weight = HT[s1].weight + HT[s2].weight;
}
}
void CreatHuffmanCode(HuffmanTree HT)
{
int start, c, f;
int i;
char* cd = new char[n];
cd[n - 1] = '\0';
cout << "字符编码为：" << endl;
for (i = 0; i < n; i++)
{
start = n - 1;
c = i;
f = HT[i].parent;
while (f != 0)
{
--start;
if (HT[f].lchild == c)
{
cd[start] = '0';
}
else
{
cd[start] = '1';
}
c = f;
f = HT[f].parent;
}
HT[i].code = new char[n - start];
strcpy(HT[i].code, &cd[start]);
cout << HT[i].letter << ":" << HT[i].code << endl;
}
delete[] cd;
}
void HuffmanTreeDecode(HuffmanTree HT, char cod[], int b)
{
char sen[100];
char temp[50];
char voidstr[] = " ";
int t = 0;
int s = 0;
int count = 0;
for (int i = 0; i < b; i++)
{
temp[t++] = cod[i];
temp[t] = '\0';
for (int j = 0; j < n; j++)
{
if (!strcmp(HT[j].code, temp))
{
sen[s] = HT[j].letter;
s++;
count += t;
strcpy(temp, voidstr);
t = 0;
break;
}
}
}
if (t == 0)
{
sen[s] = '\0';
cout << "译码为:" << endl;
cout << sen << endl;
}
else
{
cout << "二进制源码有错！从第" << count + 1 << "位开始" << endl;
}
}
int main()
{
HuffmanTree HT;
int b[100]={
0};
int i, j;
int symbol = 1, x, k;
cout << "请输入一段文字:";
cin >> buff;
int len = (int)strlen(buff);
for (i = 0; i < len; i++)
{
for (j = 0; j < n; j++)
{
if (a[j] == buff[i])
{
b[j] = b[j] + 1;
break;
}
}
if (j >= n)
{
a[n] = buff[i];
b[n] = 1;
n++;
}
}
cout << "字符和权值信息如下" << endl;
for (i = 0; i < n; i++)
{
cout << "字符：" << a[i] << " 权值：" << b[i] << endl;
}
CreateHuffmanTree(HT, a, b);
CreatHuffmanCode(HT);
cout << "文字编码为：\n";
for (int i = 0; i < len; i++)
{
for (int j = 0; j < n; j++)
{
if (buff[i] == HT[j].letter)
{
cout << HT[j].code;
break;
}
}
}
cout << "\n译码：" << endl;
while (1)
{
cout << "请输入要译码的二进制字符串,输入'#'结束：";
x = 1;
k = 0;
symbol = 1;
while (symbol)
{
cin >> p;
if (p != '1' && p != '0' && p != '#')
{
x = 0;
}
coding[k] = p;
if (p == '#')
symbol = 0;
k++;
}
if (x == 1)
{
HuffmanTreeDecode(HT, coding, k - 1);
}
else
{
cout << "有非法字符！" << endl;
}
cout << "是否继续?(Y/N):";
cin >> p;
if (p == 'y' || p == 'Y')
continue;
else
break;
}
return 0;
}
图的基本操作
实验内容
分别用邻接矩阵和邻接表对如下有向图实现：
1.输出存储结果；
2.计算各结点的出度和入度，并输出；
3.实现图的深度优先遍历和广度优先遍历，并输出。
代码实现
#include<stdio.h>
#include<stdlib.h>
#define MAXVEX 50
int visit[MAXVEX];
int in_deg[MAXVEX];//入度
int out_deg[MAXVEX];//出度
typedef struct
{
int vertices[MAXVEX];
int arc[MAXVEX][MAXVEX];
int vexnum, arcnum;
}MGraph;
typedef struct queue
{
int* pBase;
int front, rear;
}QUEUE;
void init_queue(QUEUE* Q)
{
Q->pBase = (int*)malloc((sizeof(int)) * MAXVEX);
Q->front = 0;
Q->rear = 0;
}
bool isfull_queue(QUEUE* Q)
{
if (((Q->rear + 1) % MAXVEX) == Q->front)
return true;
else
return false;
}
bool isempty_queue(QUEUE* Q)
{
if (Q->rear == Q->front)
return true;
else
return false;
}
void in_queue(QUEUE* Q, int val)
{
if (isfull_queue(Q))
return;
Q->pBase[Q->rear] = val;
Q->rear = (Q->rear + 1) % MAXVEX;
}
int out_queue(QUEUE* Q)
{
int temp = 0;
if (isempty_queue(Q))
return 0;
temp = Q->pBase[Q->front];
Q->front = (Q->front + 1) % MAXVEX;
return temp;
}
void BFS(MGraph G, QUEUE* Q, int v)
{
if (!visit[v]) {
visit[v] = 1;
printf("%d ", G.vertices[v]);
in_queue(Q, v);
}
while (!isempty_queue(Q)) {
int temp = out_queue(Q);
for (int i = 0; i < G.vexnum; i++) {
if (G.arc[temp][i] != 0 && !visit[i]) {
visit[i] = 1;
printf("%d ", G.vertices[i]);
in_queue(Q, i);
}
}
}
}
void BFST(MGraph G, QUEUE* Q)
{
printf("\nBFS的遍历：");
int i = 0;
for (i = 0; i < G.arcnum; i++)
visit[i] = 0;
for (i = 0; i < G.vexnum; i++) {
if (!visit[i]) BFS(G, Q, i);
}
}
int LocateVex(MGraph G, int v)
{
for (int i = 0; i < G.vexnum; i++) {
if (G.vertices[i] == v)
return i;
}
return 0;
}
void CreatMGraph(MGraph* G)
{
int i = 0, j = 0;
printf("请分别输入顶点数和边数： \n");
scanf("%d%d", &(G->vexnum), &(G->arcnum));
printf("请输入顶点信息：\n");
for (i = 0; i < G->vexnum; i++)
scanf("%d", &(G->vertices[i]));
for (i = 0; i < G->vexnum; i++) {
for (j = 0; j < G->vexnum; j++)
G->arc[i][j] = 0;
}
printf("请输入构成边的两个顶点: \n");
for (i = 0; i < G->arcnum; i++) {
int num, num1;
scanf("%d%d", &num, &num1);
int j = LocateVex(*G, num);
int k = LocateVex(*G, num1);
G->arc[j][k] = 1;
}
}
void PrintMGraph(MGraph G)
{
printf("*************************\n");
printf("邻接矩阵的遍历:\n");
for (int i = 0; i < G.vexnum; i++) {
for (int j = 0; j < G.vexnum; j++) {
printf("%d ", G.arc[i][j]);
if (G.arc[i][j] != 0)
out_deg[i]++;
if (G.arc[j][i] != 0)
in_deg[i]++;
}
printf("\n");
}
printf("*************************\n");
}
void Print_in_out_deg(MGraph G)
{
printf("\n*************************\n");
printf("各顶点的度的遍历:\n");
for (int i = 0; i < G.vexnum; i++) {
printf("\n第%d条边的入度: %d 与出度: %d\n", i + 1, in_deg[i], out_deg[i]);
}
printf("*************************\n");
}
void DFS(MGraph G, int v)
{
visit[v] = 1;
printf("%d ", G.vertices[v]);
for (int i = 0; i < G.vexnum; i++) {
if (G.arc[v][i] != 0 && visit[i] == 0)
DFS(G, i);
}
}
void DFST(MGraph G)
{
printf("DFS的遍历：");
for (int i = 0; i < G.vexnum; i++) {
if (!visit[i])
DFS(G, i);
}
}
int main()
{
MGraph G;
QUEUE Q;
init_queue(&Q);
CreatMGraph(&G);
PrintMGraph(G);
DFST(G);
BFST(G, &Q);
Print_in_out_deg(G);
return 0;
}