学校的数据结构试验题目二--哈夫曼树编码
终于写完了~~我觉得那个解码编码部分还能优化~~如果有更好的方法欢迎赐教~~呵呵
题目:
解法:
1
#include
<
iostream
>
2 #include < windows.h >
3 #include < tchar.h >
4
5 #define MAXVALUE 0xffff
6 using namespace std ;
7
8 typedef struct {
9 char data ;
10 int value ;
11 int parent ;
12 int lchild ;
13 int rchild ;
14 } HfmTree; // 哈夫曼树结构
15
16 typedef struct {
17 int count ;
18 char code[ 10 ] ;
19 } HfmCode , * pHfmCode; // 哈夫曼树编码时储存编码序列结构
20
21 void CreateHfm(HfmTree hfmt[] , int bufcount) // 建立哈夫曼树
22 {
23 for ( int i = 0 ; i < 2 * bufcount - 1 ; i ++ )
24 {
25 hfmt[i].parent = - 1 ;
26 hfmt[i].lchild = - 1 ;
27 hfmt[i].rchild = - 1 ;
28 }
29
30 for ( int i = 0 ; i < bufcount - 1 ; i ++ )
31 {
32 int min1 = MAXVALUE, min2 = MAXVALUE ,tem1 = 0 , tem2 = 0 ;
33
34 for ( int j = 0 ; j < bufcount + i ; j ++ ) // 找出权值最小的2个树
35 {
36 if ( hfmt[j].parent == - 1 && hfmt[j].value < min1 )
37 {
38 min2 = min1 ;
39 tem2 = tem1 ;
40 min1 = hfmt[j].value ;
41 tem1 = j ;
42 } else if ( hfmt[j].parent == - 1 && hfmt[j].value < min2)
43 {
44 min2 = hfmt[j].value ;
45 tem2 = j ;
46 }
47 }
48 // 合并树
49 hfmt[tem1].parent = bufcount + i ;
50 hfmt[tem2].parent = bufcount + i ;
51 hfmt[bufcount + i].lchild = tem1 ;
52 hfmt[bufcount + i].rchild = tem2 ;
53 hfmt[bufcount + i].value = hfmt[tem1].value + hfmt[tem2].value ;
54 }
55 }
56
57 pHfmCode GetHfmCode(HfmTree hfmt[] , char target , int bufcount) // 根据哈夫曼树编码函数
58 {
59 int pos , temp , count = 0 ;
60 pHfmCode code = new HfmCode ;
61 code -> count = 0 ;
62
63 for ( int i = 0 ; i < bufcount ; i ++ )
64 {
65 if ( hfmt[i].data == target ) // 找到目标字符在树中位置
66 {
67 pos = i ;
68 break ;
69 }
70 }
71
72 while ( 1 ) // 从叶子逆推到根节点,所得的序列倒序就是字符对应的哈夫曼编码
73 {
74 temp = hfmt[pos].parent ;
75
76 if (temp == - 1 )
77 break ;
78
79 if ( hfmt[temp].lchild == pos )
80 code -> code[count ++ ] = 0 + ' 0 ' ; // 转换成字符串存放
81 else
82 code -> code[count ++ ] = 1 + ' 0 ' ;
83
84 pos = temp ;
85 code -> count ++ ;
86 }
87
88 return code ;
89 }
90
91 void CodingBuf( char ipbuf[] , HfmTree * hfmt , int bufcount) // 讲得到的字符串进行编码,然后写入文件
92 {
93 FILE * codef ;
94
95 codef = _tfopen( " codefile.txt " , " w+ " ) ;
96
97 while ( 1 )
98 {
99 if ( * ipbuf == ' \0 ' ) // 如果字符串遍历结束就跳出循环
100 break ;
101
102 pHfmCode code = GetHfmCode(hfmt , * ipbuf , bufcount) ; // 获得哈夫曼编码
103
104 for ( int i = code -> count ; i > 0 ; i -- ) // 要倒着打印,应为之前是逆推到树根的,得到的序列也是倒序的
105 fwrite( & code -> code[i - 1 ] , sizeof ( char ) , 1 , codef ) ;
106
107 ipbuf ++ ;
108 }
109
110 fclose(codef) ;
111 }
112
113 void DecodingBuf(HfmTree hfmt[] , char codefile[] , int bufcount) // 哈夫曼解码函数
114 {
115 FILE * textf ;
116 textf = _tfopen( " textfile.txt " , " w+ " ) ;
117 char decodebuf[ 100 ] = { 0 } , * temp = codefile ;
118 int count = bufcount * 2 - 2 , i = 0 ;
119 /*
120 根据输入的编码信息,从树根开始向下遍历,
121 只要到叶子的地方就储存叶子数据,然后回到树根继续遍历
122 知道将输入的编码信息遍历完为止
123 */
124 do
125 {
126 if ( hfmt[count].data != 0 )
127 {
128 decodebuf[i ++ ] = hfmt[count].data ;
129 count = bufcount * 2 - 2 ;
130 }
131 if ( * temp == ' 0 ' )
132 count = hfmt[count].lchild ;
133 else
134 count = hfmt[count].rchild ;
135 } while ( * (temp ++ ) != ' \0 ' ) ;
136
137 fwrite(decodebuf , sizeof ( char ) , 100 , textf ) ; // 解码信息写入文件
138
139 fclose(textf) ;
140 }
141
142
143
144 int main( void )
145 {
146 FILE * hfmf , * codef , * textf ;
147 char ipbuf[ 100 ] ;
148 int bufcount = 4 ;
149 HfmTree hfmt[ 19 ] = { 0 } ;
150
151 // ----------------------------------------------信息收集部分
152 cout << " 输入终端字符集大小(1-10) " << endl ;
153 cin >> bufcount ;
154
155 for ( int i = 0 ; i < bufcount ; i ++ )
156 {
157 cout << " 请输入终端字符内容: " << endl ;
158 cin >> hfmt[i].data ;
159 cout << " 请输入终端字符权值:(0-9) " << endl ;
160 cin >> hfmt[i].value ;
161 }
162
163
164 // -----------------------------------------------建哈夫曼树部分
165 CreateHfm(hfmt ,bufcount ) ;
166
167 // 打印哈夫曼树
168 for ( int i = 0 ; i < bufcount * 2 - 1 ; i ++ )
169 {
170 cout << " id " << ' \t ' << " data " << ' \t ' << " parent " << ' \t ' << " lchild " << ' \t ' << " rchild " << ' \t ' << " value " << endl ;
171 cout << i << ' \t ' << hfmt[i].data << ' \t ' << hfmt[i].parent << ' \t ' << hfmt[i].lchild << ' \t ' << hfmt[i].rchild << ' \t ' << hfmt[i].value << endl ;
172 }
173
174 hfmf = _tfopen( " hfmtree.txt " , " w+ " ) ;
175
176
177
178 char tittle[] = " id data parent lchild rchild values " ;
179 tittle[strlen(tittle)] = ' \n ' ;
180 fwrite(tittle , sizeof ( char ) , sizeof (tittle) , hfmf ) ;
181 char data[ 1000 ] = { 0 }, * buf = data , intbuf[ 10 ] = { 0 };
182 for ( int i = 0 ; i < bufcount * 2 - 1 ; i ++ )
183 {
184 _itoa(i , intbuf , 10 ) ;
185 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
186 buf += strlen(intbuf) ;
187 * buf = ' \t ' ; buf ++ ;
188 * buf = hfmt[i].data ; buf ++ ;
189 * buf = ' \t ' ; buf ++ ;
190
191 _itoa(hfmt[i].parent , intbuf , 10 ) ;
192 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
193 buf += strlen(intbuf) ;
194 * buf = ' \t ' ; buf ++ ;
195
196 _itoa(hfmt[i].lchild , intbuf , 10 ) ;
197 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
198 buf += strlen(intbuf) ;
199 * buf = ' \t ' ; buf ++ ;
200
201 _itoa(hfmt[i].rchild , intbuf , 10 ) ;
202 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
203 buf += strlen(intbuf) ;
204 * buf = ' \t ' ; buf ++ ;
205
206 _itoa(hfmt[i].value , intbuf , 10 ) ;
207 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
208 buf += strlen(intbuf) ;
209 * buf = ' \n ' ; buf ++ ;
210
211 }
212 fwrite(data , sizeof ( char ) , 1000 , hfmf );
213
214 cout << buf << endl ;
215 // -----------------------------------------------编码部分
216 cout << " 输入要编码的字符串 " << endl ;
217 cin >> ipbuf ;
218
219 CodingBuf(ipbuf , hfmt , bufcount ) ;
220
221 codef = _tfopen( " codefile.txt " , " r+ " ) ;
222 char codefile[ 100 ] = { 0 };
223
224 fread(codefile , sizeof ( char ) , 100 , codef) ;
225
226 cout << " 编码结果 " << endl ;
227 cout << codefile << endl ;
228
229 system( " pause " ) ;
230 // -----------------------------------------------解码部分
231 cout << " 解码ING![]()
![]()
"
<<
endl ;
232 DecodingBuf(hfmt , codefile , bufcount ) ;
233
234 cout << " 解码结果: " << endl ;
235 textf = _tfopen( " textfile.txt " , " r+ " ) ;
236 memset(codefile , 0 , 100 ) ;
237
238 fread(codefile , sizeof ( char ) , 100 , textf ) ;
239
240 cout << codefile << endl ;
241
242 system( " pause " ) ;
243
244
245
246 fclose( textf ) ;
247 fclose( hfmf ) ;
248 fclose(codef) ;
249 return 1 ;
250
251 }
252
253
254
2 #include < windows.h >
3 #include < tchar.h >
4
5 #define MAXVALUE 0xffff
6 using namespace std ;
7
8 typedef struct {
9 char data ;
10 int value ;
11 int parent ;
12 int lchild ;
13 int rchild ;
14 } HfmTree; // 哈夫曼树结构
15
16 typedef struct {
17 int count ;
18 char code[ 10 ] ;
19 } HfmCode , * pHfmCode; // 哈夫曼树编码时储存编码序列结构
20
21 void CreateHfm(HfmTree hfmt[] , int bufcount) // 建立哈夫曼树
22 {
23 for ( int i = 0 ; i < 2 * bufcount - 1 ; i ++ )
24 {
25 hfmt[i].parent = - 1 ;
26 hfmt[i].lchild = - 1 ;
27 hfmt[i].rchild = - 1 ;
28 }
29
30 for ( int i = 0 ; i < bufcount - 1 ; i ++ )
31 {
32 int min1 = MAXVALUE, min2 = MAXVALUE ,tem1 = 0 , tem2 = 0 ;
33
34 for ( int j = 0 ; j < bufcount + i ; j ++ ) // 找出权值最小的2个树
35 {
36 if ( hfmt[j].parent == - 1 && hfmt[j].value < min1 )
37 {
38 min2 = min1 ;
39 tem2 = tem1 ;
40 min1 = hfmt[j].value ;
41 tem1 = j ;
42 } else if ( hfmt[j].parent == - 1 && hfmt[j].value < min2)
43 {
44 min2 = hfmt[j].value ;
45 tem2 = j ;
46 }
47 }
48 // 合并树
49 hfmt[tem1].parent = bufcount + i ;
50 hfmt[tem2].parent = bufcount + i ;
51 hfmt[bufcount + i].lchild = tem1 ;
52 hfmt[bufcount + i].rchild = tem2 ;
53 hfmt[bufcount + i].value = hfmt[tem1].value + hfmt[tem2].value ;
54 }
55 }
56
57 pHfmCode GetHfmCode(HfmTree hfmt[] , char target , int bufcount) // 根据哈夫曼树编码函数
58 {
59 int pos , temp , count = 0 ;
60 pHfmCode code = new HfmCode ;
61 code -> count = 0 ;
62
63 for ( int i = 0 ; i < bufcount ; i ++ )
64 {
65 if ( hfmt[i].data == target ) // 找到目标字符在树中位置
66 {
67 pos = i ;
68 break ;
69 }
70 }
71
72 while ( 1 ) // 从叶子逆推到根节点,所得的序列倒序就是字符对应的哈夫曼编码
73 {
74 temp = hfmt[pos].parent ;
75
76 if (temp == - 1 )
77 break ;
78
79 if ( hfmt[temp].lchild == pos )
80 code -> code[count ++ ] = 0 + ' 0 ' ; // 转换成字符串存放
81 else
82 code -> code[count ++ ] = 1 + ' 0 ' ;
83
84 pos = temp ;
85 code -> count ++ ;
86 }
87
88 return code ;
89 }
90
91 void CodingBuf( char ipbuf[] , HfmTree * hfmt , int bufcount) // 讲得到的字符串进行编码,然后写入文件
92 {
93 FILE * codef ;
94
95 codef = _tfopen( " codefile.txt " , " w+ " ) ;
96
97 while ( 1 )
98 {
99 if ( * ipbuf == ' \0 ' ) // 如果字符串遍历结束就跳出循环
100 break ;
101
102 pHfmCode code = GetHfmCode(hfmt , * ipbuf , bufcount) ; // 获得哈夫曼编码
103
104 for ( int i = code -> count ; i > 0 ; i -- ) // 要倒着打印,应为之前是逆推到树根的,得到的序列也是倒序的
105 fwrite( & code -> code[i - 1 ] , sizeof ( char ) , 1 , codef ) ;
106
107 ipbuf ++ ;
108 }
109
110 fclose(codef) ;
111 }
112
113 void DecodingBuf(HfmTree hfmt[] , char codefile[] , int bufcount) // 哈夫曼解码函数
114 {
115 FILE * textf ;
116 textf = _tfopen( " textfile.txt " , " w+ " ) ;
117 char decodebuf[ 100 ] = { 0 } , * temp = codefile ;
118 int count = bufcount * 2 - 2 , i = 0 ;
119 /*
120 根据输入的编码信息,从树根开始向下遍历,
121 只要到叶子的地方就储存叶子数据,然后回到树根继续遍历
122 知道将输入的编码信息遍历完为止
123 */
124 do
125 {
126 if ( hfmt[count].data != 0 )
127 {
128 decodebuf[i ++ ] = hfmt[count].data ;
129 count = bufcount * 2 - 2 ;
130 }
131 if ( * temp == ' 0 ' )
132 count = hfmt[count].lchild ;
133 else
134 count = hfmt[count].rchild ;
135 } while ( * (temp ++ ) != ' \0 ' ) ;
136
137 fwrite(decodebuf , sizeof ( char ) , 100 , textf ) ; // 解码信息写入文件
138
139 fclose(textf) ;
140 }
141
142
143
144 int main( void )
145 {
146 FILE * hfmf , * codef , * textf ;
147 char ipbuf[ 100 ] ;
148 int bufcount = 4 ;
149 HfmTree hfmt[ 19 ] = { 0 } ;
150
151 // ----------------------------------------------信息收集部分
152 cout << " 输入终端字符集大小(1-10) " << endl ;
153 cin >> bufcount ;
154
155 for ( int i = 0 ; i < bufcount ; i ++ )
156 {
157 cout << " 请输入终端字符内容: " << endl ;
158 cin >> hfmt[i].data ;
159 cout << " 请输入终端字符权值:(0-9) " << endl ;
160 cin >> hfmt[i].value ;
161 }
162
163
164 // -----------------------------------------------建哈夫曼树部分
165 CreateHfm(hfmt ,bufcount ) ;
166
167 // 打印哈夫曼树
168 for ( int i = 0 ; i < bufcount * 2 - 1 ; i ++ )
169 {
170 cout << " id " << ' \t ' << " data " << ' \t ' << " parent " << ' \t ' << " lchild " << ' \t ' << " rchild " << ' \t ' << " value " << endl ;
171 cout << i << ' \t ' << hfmt[i].data << ' \t ' << hfmt[i].parent << ' \t ' << hfmt[i].lchild << ' \t ' << hfmt[i].rchild << ' \t ' << hfmt[i].value << endl ;
172 }
173
174 hfmf = _tfopen( " hfmtree.txt " , " w+ " ) ;
175
176
177
178 char tittle[] = " id data parent lchild rchild values " ;
179 tittle[strlen(tittle)] = ' \n ' ;
180 fwrite(tittle , sizeof ( char ) , sizeof (tittle) , hfmf ) ;
181 char data[ 1000 ] = { 0 }, * buf = data , intbuf[ 10 ] = { 0 };
182 for ( int i = 0 ; i < bufcount * 2 - 1 ; i ++ )
183 {
184 _itoa(i , intbuf , 10 ) ;
185 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
186 buf += strlen(intbuf) ;
187 * buf = ' \t ' ; buf ++ ;
188 * buf = hfmt[i].data ; buf ++ ;
189 * buf = ' \t ' ; buf ++ ;
190
191 _itoa(hfmt[i].parent , intbuf , 10 ) ;
192 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
193 buf += strlen(intbuf) ;
194 * buf = ' \t ' ; buf ++ ;
195
196 _itoa(hfmt[i].lchild , intbuf , 10 ) ;
197 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
198 buf += strlen(intbuf) ;
199 * buf = ' \t ' ; buf ++ ;
200
201 _itoa(hfmt[i].rchild , intbuf , 10 ) ;
202 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
203 buf += strlen(intbuf) ;
204 * buf = ' \t ' ; buf ++ ;
205
206 _itoa(hfmt[i].value , intbuf , 10 ) ;
207 memcpy(buf , intbuf , strlen(intbuf) * sizeof ( char ) ) ;
208 buf += strlen(intbuf) ;
209 * buf = ' \n ' ; buf ++ ;
210
211 }
212 fwrite(data , sizeof ( char ) , 1000 , hfmf );
213
214 cout << buf << endl ;
215 // -----------------------------------------------编码部分
216 cout << " 输入要编码的字符串 " << endl ;
217 cin >> ipbuf ;
218
219 CodingBuf(ipbuf , hfmt , bufcount ) ;
220
221 codef = _tfopen( " codefile.txt " , " r+ " ) ;
222 char codefile[ 100 ] = { 0 };
223
224 fread(codefile , sizeof ( char ) , 100 , codef) ;
225
226 cout << " 编码结果 " << endl ;
227 cout << codefile << endl ;
228
229 system( " pause " ) ;
230 // -----------------------------------------------解码部分
231 cout << " 解码ING
232 DecodingBuf(hfmt , codefile , bufcount ) ;
233
234 cout << " 解码结果: " << endl ;
235 textf = _tfopen( " textfile.txt " , " r+ " ) ;
236 memset(codefile , 0 , 100 ) ;
237
238 fread(codefile , sizeof ( char ) , 100 , textf ) ;
239
240 cout << codefile << endl ;
241
242 system( " pause " ) ;
243
244
245
246 fclose( textf ) ;
247 fclose( hfmf ) ;
248 fclose(codef) ;
249 return 1 ;
250
251 }
252
253
254