根据输入的广义表建立子女右兄弟链的二叉树表示,该二叉树对应于广义表对应的普通树。先考虑更复杂的情形,如果广义表中存在共享表,则将其转换为带共享子树的二叉树表示,每一共享子树带有附加头节点,其左链指针指向共享子树,最后输出带共享子树的子女右兄弟链表示(广义表形式)
C++代码:
1 #include "stdafx.h" 2 #include <iostream> 3 #include <stack> 4 #include <string> 5 #include <map> 6 #include <vector> 7 using namespace std; 8 9 class Dnode //二叉树节点类 10 { 11 public: 12 char data; 13 Dnode *left; 14 Dnode *right; 15 Dnode(char d = ‘\0‘) :data(d), left(nullptr), right(nullptr) {} 16 }; 17 18 class info 19 { 20 public: 21 vector<int> left; 22 vector<int> right; 23 Dnode *share = nullptr; 24 vector<int>::size_type position = 0; 25 }; 26 27 int Searchd(Dnode *ptr, int d); 28 void creatsharelist(string &glist, map<string, info> &sharelist); 29 map<string, info>::iterator Searchshare(int left, map<string, info> &sharelist); 30 31 int main() 32 { 33 cout << "请输入广义表字符串形式" << endl; 34 string glist; 35 cin >> glist; //输入广义表 36 37 map<string, info> sharelist; 38 creatsharelist(glist, sharelist); 39 40 stack<Dnode *> arrange; 41 Dnode *ptr = nullptr; 42 43 map<string, info>::iterator p; 44 for (string::size_type i = 0; i != glist.size(); i++) //由广义表建子女右兄弟链二叉树 45 { 46 if (glist[i] == ‘(‘) 47 { 48 if (i == 0) 49 { 50 ptr = new Dnode(); 51 arrange.push(ptr); 52 } 53 else 54 { 55 Dnode *temp = new Dnode(); 56 if (arrange.top() == ptr) 57 { 58 if (arrange.size() != 1) 59 { 60 if (p != sharelist.end()) 61 { 62 p->second.share = temp; 63 } 64 } 65 ptr->left=temp; 66 } 67 else 68 { 69 ptr->right = temp; 70 } 71 ptr = temp; 72 73 if (glist[i + 1] != ‘)‘) 74 { 75 p = Searchshare(i + 1, sharelist); 76 if (p != sharelist.end()) 77 { 78 if (p->second.share != nullptr) 79 { 80 i = p->second.right[p->second.position - 1] - 1; 81 temp->left = p->second.share; 82 continue; 83 } 84 } 85 } 86 arrange.push(ptr); 87 } 88 } 89 else 90 { 91 if (glist[i] == ‘)‘) 92 { 93 ptr = arrange.top(); 94 arrange.pop(); 95 } 96 else 97 { 98 if (glist[i] != ‘,‘) 99 { 100 Dnode *temp = new Dnode(glist[i]); 101 if (ptr == arrange.top()) 102 { 103 if (p != sharelist.end()) 104 { 105 p->second.share = temp; 106 } 107 ptr->left = temp; 108 } 109 else 110 ptr->right = temp; 111 ptr = temp; 112 } 113 } 114 } 115 } 116 //ptr指向二叉树根节点 117 cout << "已将广义表字符串形式转化为子女右兄弟链表示" << endl; 118 cout << "子女右兄弟链表示对应的广义表形式为:"; 119 cout << "("; 120 121 int d = 0; 122 Dnode *const dest = ptr; 123 while (true) //输出子女右兄弟链二叉树对应广义表形式 124 { 125 if (Searchd(ptr, d) == 0) 126 { 127 if (ptr == dest) 128 { 129 if (d==0) 130 cout << ‘)‘; 131 break; 132 } 133 else 134 { 135 if (d == 0) 136 { 137 if (ptr->data == ‘\0‘) 138 cout << "()"; 139 else 140 cout << ptr->data; 141 cout << ")"; 142 } 143 else 144 { 145 cout << ")"; 146 } 147 ptr = arrange.top(); 148 d = 1; 149 arrange.pop(); 150 } 151 } 152 else 153 { 154 Dnode *interval = nullptr; 155 if (d == 0) 156 { 157 if (ptr->left != nullptr) 158 { 159 if (ptr != dest) 160 cout << "("; 161 arrange.push(ptr); 162 interval = ptr->left; 163 } 164 else 165 { 166 if (ptr->data == ‘\0‘) 167 { 168 cout << "()"; 169 } 170 else 171 { 172 cout << ptr->data; 173 } 174 cout << ","; 175 interval = ptr->right; 176 } 177 } 178 else 179 { 180 cout << ","; 181 interval = ptr->right; 182 } 183 d = 0; 184 ptr = interval; 185 } 186 } 187 return 0; 188 } 189 190 int Searchd(Dnode *ptr, int d) 191 { 192 if (d == 2) 193 return 0; 194 else 195 { 196 if (d == 1) 197 { 198 if (ptr->right == nullptr) 199 return 0; 200 else 201 return 2; 202 } 203 else 204 { 205 if (ptr->left != nullptr) 206 return 1; 207 else 208 { 209 if (ptr->right != nullptr) 210 return 2; 211 else 212 return 0; 213 } 214 } 215 } 216 } 217 218 void creatsharelist(string &glist, map<string, info> &sharelist) 219 { 220 vector<int> stack; 221 int total = 0; 222 for (const auto &s : glist) 223 { 224 if (s == ‘(‘) 225 { 226 ++total; 227 stack.push_back(total); 228 } 229 else if (s == ‘)‘) 230 { 231 ++total; 232 string temp = glist.substr(stack[stack.size() - 1] - 1, total - stack[stack.size() - 1] + 1); 233 auto p = sharelist.find(temp); 234 if (p == sharelist.end()) 235 { 236 auto q = sharelist.insert(make_pair(temp, *(new info))); 237 q.first->second.left.push_back(stack[stack.size() - 1]); 238 q.first->second.right.push_back(total); 239 } 240 else 241 { 242 p->second.left.push_back(stack[stack.size() - 1]); 243 p->second.right.push_back(total); 244 } 245 stack.pop_back(); 246 } 247 else 248 { 249 ++total; 250 } 251 } 252 253 auto m = sharelist.begin(); 254 while (m != sharelist.end()) 255 { 256 if (m->second.left.size() == 1 || m->first=="()") 257 m = sharelist.erase(m); 258 else 259 ++m; 260 } 261 } 262 263 map<string, info>::iterator Searchshare(int left, map<string, info> &sharelist) 264 { 265 auto p = sharelist.begin(); 266 for (; p != sharelist.end(); ++p) 267 { 268 if (p->second.left.size() != p->second.position && p->second.left[p->second.position] == left) 269 { 270 ++p->second.position; 271 return p; 272 } 273 } 274 return p; 275 }
运行结果:
广义表无共享表情形相对简单:
1 #include "stdafx.h" 2 #include <iostream> 3 #include <stack> 4 #include <string> 5 using namespace std; 6 7 class Dnode 8 { 9 public: 10 char data; 11 Dnode *left; 12 Dnode *right; 13 Dnode(char d = ‘\0‘) :data(d), left(nullptr), right(nullptr) {} 14 }; 15 int Searchd(Dnode *ptr, int d); 16 17 int main() 18 { 19 cout << "请输入广义表字符串形式" << endl; 20 string glist; 21 cin >> glist; 22 stack<Dnode *> arrange; 23 Dnode *ptr = nullptr; 24 25 for (string::size_type i = 0; i != glist.size(); i++) 26 { 27 if (glist[i] == ‘(‘) 28 { 29 if (i == 0) 30 { 31 ptr = new Dnode(); 32 arrange.push(ptr); 33 } 34 else 35 { 36 Dnode *temp = new Dnode(); 37 if (arrange.top() == ptr) 38 { 39 ptr->left=temp; 40 } 41 else 42 { 43 ptr->right = temp; 44 } 45 ptr = temp; 46 arrange.push(ptr); 47 } 48 } 49 else 50 { 51 if (glist[i] == ‘)‘) 52 { 53 ptr = arrange.top(); 54 arrange.pop(); 55 } 56 else 57 { 58 if (glist[i] != ‘,‘) 59 { 60 Dnode *temp = new Dnode(glist[i]); 61 if (ptr == arrange.top()) 62 ptr->left = temp; 63 else 64 ptr->right = temp; 65 ptr = temp; 66 } 67 } 68 } 69 } 70 //ptr指向二叉树根节点 71 cout << "已将广义表字符串形式转化为子女右兄弟链表示" << endl; 72 cout << "子女右兄弟链表示对应的广义表形式为:"; 73 cout << "("; 74 75 int d = 0; 76 Dnode *const dest = ptr; 77 while (true) 78 { 79 if (Searchd(ptr, d) == 0) 80 { 81 if (ptr == dest) 82 { 83 if (d==0) 84 cout << ‘)‘; 85 break; 86 } 87 else 88 { 89 if (d == 0) 90 { 91 if (ptr->data == ‘\0‘) 92 cout << "()"; 93 else 94 cout << ptr->data; 95 cout << ")"; 96 } 97 else 98 { 99 cout << ")"; 100 } 101 ptr = arrange.top(); 102 d = 1; 103 arrange.pop(); 104 } 105 } 106 else 107 { 108 Dnode *interval = nullptr; 109 if (d == 0) 110 { 111 if (ptr->left != nullptr) 112 { 113 if (ptr != dest) 114 cout << "("; 115 arrange.push(ptr); 116 interval = ptr->left; 117 } 118 else 119 { 120 if (ptr->data == ‘\0‘) 121 { 122 cout << "()"; 123 } 124 else 125 { 126 cout << ptr->data; 127 } 128 cout << ","; 129 interval = ptr->right; 130 } 131 } 132 else 133 { 134 cout << ","; 135 interval = ptr->right; 136 } 137 d = 0; 138 ptr = interval; 139 } 140 } 141 return 0; 142 } 143 144 int Searchd(Dnode *ptr, int d) 145 { 146 if (d == 2) 147 return 0; 148 else 149 { 150 if (d == 1) 151 { 152 if (ptr->right == nullptr) 153 return 0; 154 else 155 return 2; 156 } 157 else 158 { 159 if (ptr->left != nullptr) 160 return 1; 161 else 162 { 163 if (ptr->right != nullptr) 164 return 2; 165 else 166 return 0; 167 } 168 } 169 } 170 }
运行结果: