数据结构实验：一元多项式计算器（C++ 实现）

关键字：数据结构，链表，一元多项式

代码清单：

1. main.cpp
2. Elem.h
3. Elem.cpp
4. List.h
5. List.cpp
6. Polyn.h
7. Polyn.cpp

Windows7 64位下 Code::Blocks12.11 GCC 编译运行通过。

原文地址：http://www.cnblogs.com/fengzy/archive/2013/06/01/3113039.html

欢迎交流学习，转载请注明出处。如有问题，请留言。

下面是源代码。

1. main.cpp

1 //----- main.cpp ------
 2 #include <iostream>
 3 #include <cassert>
 4 #include <stdlib.h>
 5 #include "Polyn.h"
 6 
 7 using namespace std;
 8 
 9 #define PRINT(x) cout << #x << " = " << (x)
10 #define READ(x) cout << #x << "'s SIZE: "; (x).read()
11 
12 int main()
13 {
14     Polyn Pa, Pb;
15 
16     READ(Pa);
17     READ(Pb);
18 
19     system("cls");
20 
21     PRINT(Pa);
22     PRINT(Pb);
23 
24     PRINT(Pa + Pb);
25     PRINT(Pa - Pb);
26     PRINT(Pb - Pa);
27     PRINT(Pa * Pb);
28 
29     return 0;
30 }

View Code

1. Elem.h

1 //----- Elem.h -----
 2 #ifndef ELEM_H
 3 #define ELEM_H
 4 
 5 #include <iostream>
 6 using namespace std;
 7 
 8 class Elem
 9 {
10 public:
11     Elem()
12         : coef(0.0), expn(0)
13     {
14     }
15 
16     Elem(float co, int ex)
17         : coef(co), expn(ex)
18     {
19     }
20 
21     ~Elem() {}
22 
23     float getCoef() {
24         return coef;
25     }
26 
27     void setCoef(float val) {
28         coef = val;
29     }
30 
31     int getExpn() {
32         return expn;
33     }
34 
35     void setExpn(int val) {
36         expn = val;
37     }
38 
39     const bool operator==(const Elem rightSide);
40 
41     const bool operator<=(const Elem rightSide);
42     // 仅比较指数
43 
44     const bool operator>=(const Elem rightSide);
45     // 仅比较指数
46 
47     const bool similar(const Elem rightSide);
48     //判断是否同类项，即指数相同
49 
50     void display(ostream &out) const;
51     // 打印本项（为了方便多项式输出打印系数的绝对值）
52 
53 protected:
54 private:
55     float coef; //!< 系数 "coef"
56     int expn; //!< 指数 "expn"
57 };
58 
59 ostream &operator<<(ostream &out, const Elem &aElem);
60 //istream &operator>>(istream &in, Elem &aElem);
61 
62 #endif // ELEM_H

View Code

1. Elem.cpp

1 //----- Elem.cpp -----
 2 #include <iostream>
 3 #include <cmath>
 4 using namespace std;
 5 #include "Elem.h"
 6 
 7 const bool Elem::operator==(const Elem rightSide)
 8 {
 9     return rightSide.coef == coef && rightSide.expn == expn;
10 }
11 
12 const bool Elem::operator<=(const Elem rightSide)
13 {
14     return expn <= rightSide.expn;
15 }
16 // 仅比较指数
17 
18 const bool Elem::operator>=(const Elem rightSide)
19 {
20     return expn >= rightSide.expn;
21 }
22 // 仅比较指数
23 
24 const bool Elem::similar(const Elem rightSide)
25 {
26     return expn == rightSide.expn;
27 }
28 //判断是否同类项，即指数相同
29 
30 void Elem::display(ostream &out) const
31 {
32     if (abs(coef))
33     {
34         if (abs(coef) == 1.0)
35         {
36             if (expn)
37             {
38                 if (expn > 0)
39                 {    // 指数 > 0
40                     if (expn == 1)
41                     {
42                         out << "x";
43                     }
44                     else
45                     {
46                         out << "x^" << expn;
47                     }
48                 }
49                 else
50                 {    // 指数 < 0
51                     out << "x^(" << expn << ")";
52                 }
53             }
54             else out << 1;  // 指数 = 0
55         }
56         else
57         {
58             if (expn)
59             {
60                 if (expn > 0)
61                 {    // 指数 > 0
62                     if (expn == 1)
63                     {
64                         out << abs(coef) << "x";
65                     }
66                     else
67                     {
68                         out << abs(coef) << "x^" << expn;
69                     }
70                 }
71                 else
72                 {    // 指数 < 0
73                     out << abs(coef) << "x^(" << expn << ")";
74                 }
75             }
76             else out << abs(coef); // 指数 = 0
77         }
78     }
79     else out << "0";
80 }
81 
82 ostream &operator<<(ostream &out, const Elem &aElem)
83 {
84     aElem.display(out);
85     return out;
86 }
87 
88 //istream &operator>>(istream &in, Elem &aElem)
89 //{
90 //    in
91 //    return in;
92 //}

View Code

1. List.h

1 //----- List.h -----
  2 #ifndef LINKEDLIST
  3 #define LINKEDLIST
  4 
  5 #include <iostream>
  6 #include "Elem.h"
  7 
  8 using namespace std;
  9 
 10 
 11 class List
 12 {
 13 protected:
 14     class Node
 15     {
 16     public:
 17         //------ Node 数据成员
 18         Elem data;
 19         Node   *next;
 20 
 21         //------ Node 成员函数
 22         //-- 默认构造函数:  头结点为 0
 23         Node()
 24             : next(0)
 25         { }
 26 
 27         //-- 赋值构造函数，用给定的值初始化，并将头结点置为 0
 28         Node(Elem dataValue)
 29             : data(dataValue), next(0)  // TODO maybe problems
 30         { }
 31     }; //--- end of Node class
 32 
 33     typedef Node *NodePointer;
 34 
 35 public:
 36     //------ List 成员函数
 37     List();
 38     //默认构造函数: 创建一个空链表。
 39 
 40     List(const List &origList);
 41     //复制构造函数
 42 
 43     ~List();
 44 
 45     const List &operator=(const List &rightSide);
 46     //重载赋值运算符
 47 
 48     bool empty();
 49     //判空函数
 50 
 51     void insert(Elem dataVal, int index);
 52     //向链表的指定位置插入一个元素
 53 
 54     void erase(int index);
 55     //删除指定位置的元素
 56 
 57     int search(Elem dataVal);
 58     /*--------------------------------------------------------------------
 59       查找链表中找的元素
 60       前置条件:  元素类型需重载 “==”
 61       后置条件: 返回给定元素在链表中首次出现的位置（从 0 开始）
 62           如果链表中不存在该元素，则返回 -1
 63     --------------------------------------------------------------------*/
 64 
 65     Elem getElem(int index) const;
 66     /*-------------------------------------------------------------------
 67       取得链表中指定位置的元素
 68       前置条件：指定位置 index 需满足 0< index < mySize
 69       后置条件：返回给定位置的元素
 70     --------------------------------------------------------------------*/
 71 
 72     void setElem(Elem dataVal, int index);
 73     /*-------------------------------------------------------------------
 74       改变链表中指定位置的元素
 75       前置条件：指定位置 index 需满足 0 < index < mySize，元素类型需重载
 76             赋值符号 “=”
 77       后置条件：返回给定位置的元素
 78     --------------------------------------------------------------------*/
 79 
 80     void display(ostream &out) const;
 81 
 82     int nodeCount() const;
 83     // 查询链表中节点的个数
 84 
 85     void reverse();
 86     // 逆序
 87 
 88     bool ascendingOrder();
 89     /*--------------------------------------------------------------------
 90       检查链表中元素是否升序排列
 91       前置条件:  元素类型需重载 “<=” 和 “>=”
 92     --------------------------------------------------------------------*/
 93 
 94     bool descendingOrder();
 95     /*--------------------------------------------------------------------
 96       检查链表中元素是否降序排列
 97       前置条件:  元素类型需重载 “<=” 和 “>=”
 98     --------------------------------------------------------------------*/
 99 
100 protected:
101     //------ 数据成员
102     NodePointer first;
103     int mySize;
104 }; //--- end of List class
105 
106 ostream &operator<<(ostream &out, const List &aList);
107 //istream &operator>>(istream &in, List &aList);
108 
109 #endif

View Code

1. List.cpp

1 //----- List.cpp -----
  2 #include <iostream>
  3 #include <cassert>
  4 
  5 using namespace std;
  6 #include "List.h"
  7 
  8 //-- 默认构造函数
  9 List::List()
 10     : first(0), mySize(0)
 11 { }
 12 
 13 //-- 复制构造函数
 14 List::List(const List &origList)
 15 {
 16     mySize = origList.mySize;
 17     first = 0;
 18 
 19     if (mySize == 0) return;
 20 
 21     List::NodePointer origPtr, lastPtr;
 22     first = new Node(origList.first->data);  // 复制头结点
 23     lastPtr = first;
 24     origPtr = origList.first->next;
 25 
 26     while (origPtr != 0)
 27     {
 28         lastPtr->next = new Node(origPtr->data);
 29         origPtr = origPtr->next;
 30         lastPtr = lastPtr->next;
 31     }
 32 }
 33 
 34 //-- 析构函数
 35 List::~List()
 36 {
 37     List::NodePointer prev = first,
 38                       ptr;
 39 
 40     while (prev != 0)
 41     {
 42         ptr = prev->next;
 43         delete prev;
 44         prev = ptr;
 45     }
 46 }
 47 
 48 bool List::empty()
 49 {
 50     return mySize == 0;
 51 }
 52 
 53 //-- 赋值运算符
 54 const List &List::operator=(const List &rightSide)
 55 {
 56     mySize = rightSide.mySize;
 57     first = 0;
 58 
 59     if (mySize == 0) return *this;
 60 
 61     if (this != &rightSide)
 62     {
 63         this->~List();
 64         List::NodePointer origPtr, lastPtr;
 65         first = new Node(rightSide.first->data);  // 复制头结点
 66         lastPtr = first;
 67         origPtr = rightSide.first->next;
 68 
 69         while (origPtr != 0)
 70         {
 71             lastPtr->next = new Node(origPtr->data);
 72             origPtr = origPtr->next;
 73             lastPtr = lastPtr->next;
 74         }
 75     }
 76 
 77     return *this;
 78 }
 79 
 80 void List::insert(Elem dataVal, int index)
 81 {
 82     if (index < 0 || index > mySize)
 83     {
 84         cerr << "Illegal location to insert -- " << index
 85              << ", size of the link is " << mySize << ".n";
 86 
 87         assert (index >= 0 && index <= mySize);
 88     }
 89 
 90     mySize++;
 91     List::NodePointer newPtr = new Node(dataVal),
 92     predPtr = first;
 93 
 94     if (index == 0)
 95     {
 96         newPtr->next = first;
 97         first = newPtr;
 98     }
 99     else
100     {
101         for(int i = 1; i < index; i++)
102             predPtr = predPtr->next;
103 
104         newPtr->next = predPtr->next;
105         predPtr->next = newPtr;
106     }
107 }
108 
109 void List::erase(int index)
110 {
111     if (index < 0 || index >= mySize)
112     {
113         cerr << "Illegal location to delete -- " << index
114              << ", size of the link is " << mySize << ".n";
115 
116         assert (index >= 0 && index <= mySize);
117     }
118 
119     mySize--;
120     List::NodePointer ptr,
121          predPtr = first;
122 
123     if (index == 0)
124     {
125         ptr = first;
126         first = ptr->next;
127         delete ptr;
128     }
129     else
130     {
131         for(int i = 1; i < index; i++)
132             predPtr = predPtr->next;
133 
134         ptr = predPtr->next;
135         predPtr->next = ptr->next;
136         delete ptr;
137     }
138 }
139 
140 int List::search(Elem dataVal)
141 {
142     int loc;
143     List::NodePointer tempP = first;
144 
145     for (loc = 0; loc < mySize; loc++)
146         if (tempP->data == dataVal)
147             return loc;
148         else
149             tempP = tempP->next;
150 
151     return -1;
152 }
153 
154 void List::display(ostream &out) const
155 {
156     List::NodePointer ptr = first;
157 
158     while (ptr != 0)
159     {
160         out << ptr->data << "  ";
161         ptr = ptr->next;
162     }
163 }
164 
165 ostream &operator<<(ostream &out, const List &aList)
166 {
167     aList.display(out);
168     return out;
169 }
170 
171 int List::nodeCount() const
172 {
173     // or simply,  { return mySize; }
174     int count = 0;
175     List::NodePointer ptr = first;
176 
177     while (ptr != 0)
178     {
179         count++;
180         ptr = ptr->next;
181     }
182 
183     return count;
184 }
185 
186 void List::reverse()
187 {
188     NodePointer prevP = 0,
189                 currentP = first,
190                 nextP;
191 
192     while (currentP != 0)
193     {
194         nextP = currentP->next;
195         currentP->next = prevP;
196         prevP = currentP;
197         currentP = nextP;
198     }
199 
200     first = prevP;      // new head of (reversed) linked list
201 }
202 
203 bool List::ascendingOrder()
204 {
205     if (mySize <= 1)
206         //empty or one element list
207         return true;
208 
209     //else
210     NodePointer prevP = first,
211                 tempP = first->next;
212 
213     while (tempP != 0 && prevP->data <= tempP->data)
214     {
215         prevP = tempP;
216         tempP = tempP->next;
217     }
218 
219     if (tempP != 0)
220         return false;
221 
222     // else
223     return true;
224 }
225 
226 bool List::descendingOrder()
227 {
228     if (mySize <= 1)
229         //empty or one element list
230         return true;
231 
232     //else
233     NodePointer prevP = first,
234                 tempP = first->next;
235 
236     while (tempP != 0 && prevP->data >= tempP->data)
237     {
238         prevP = tempP;
239         tempP = tempP->next;
240     }
241 
242     if (tempP != 0)
243         return false;
244 
245     // else
246     return true;
247 }
248 
249 Elem List::getElem(int index) const
250 {
251     if (index < 0 || index >= mySize)
252     {
253         cerr << "Illegal location to get element -- " << index
254              << ", size of the link is " << mySize << ".n";
255 
256         assert (index >= 0 && index <= mySize);
257     }
258 
259 
260 
261     if (index == 0)
262         return first->data;
263     else
264     {
265         List::NodePointer ptr = first;
266 
267         for(int i = 1; i < index; i++)
268             ptr = ptr->next;
269 
270         return ptr->next->data;
271     }
272 }
273 
274 void List::setElem(Elem dataVal, int index)
275 {
276     if (index < 0 || index >= mySize)
277     {
278         cerr << "Illegal location to set element -- " << index
279              << ", size of the link is " << mySize << ".n";
280 
281         assert (index >= 0 && index <= mySize);
282     }
283 
284     if (index == 0)
285         first->data = dataVal;
286     else
287     {
288         List::NodePointer ptr = first;
289 
290         for(int i = 1; i < index; i++)
291             ptr = ptr->next;
292 
293         ptr->next->data = dataVal;
294     }
295 
296 }

View Code

1. Polyn.h

1 //----- Polyn.h ------
 2 #ifndef POLYN_H
 3 #define POLYN_H
 4 
 5 #include "List.h"
 6 
 7 class Polyn : public List
 8 {
 9 public:
10     void read();
11     void display(ostream &out) const;
12     void mergerCo();    // 合并指数相同的项
13     void sort();        // 按指数降序排序
14     Polyn operator+(const Polyn &b);
15     Polyn operator-(const Polyn &b);
16     Polyn operator*(const Polyn &b);
17 
18 protected:
19 private:
20 };
21 
22 ostream &operator<<(ostream &out, const Polyn &aPolyn);
23 
24 #endif // POLYN_H

View Code

1. Polyn.cpp

1 //----- Polyn.h ------
 2 #ifndef POLYN_H
 3 #define POLYN_H
 4 
 5 #include "List.h"
 6 
 7 class Polyn : public List
 8 {
 9 public:
10     void read();
11     void display(ostream &out) const;
12     void mergerCo();    // 合并指数相同的项
13     void sort();        // 按指数降序排序
14     Polyn operator+(const Polyn &b);
15     Polyn operator-(const Polyn &b);
16     Polyn operator*(const Polyn &b);
17 
18 protected:
19 private:
20 };
21 
22 ostream &operator<<(ostream &out, const Polyn &aPolyn);
23 
24 #endif // POLYN_H

View Code

测试数据：

测试用例：

(1) 
    3
    2 1 5 8 -3.1 11
    3
    7 0 -5 8 11 9

(2) 
    4
    6 -3 -1 1 4.4 2 -1.2 9
    4
    -6 -3 5.4 2 -1 2 7.8 15

(3) 
    6
    1 0 1 1 1 2 1 3 1 4 1 5
    2
    -1 3 -1 4

(4) 
    2
    1 1 1 3
    2
    -1 1 -1 3

(5)
    2
    1 1 1 100
    1 100 1 200

(6)
    3
    1 1 1 2 1 3
    1
    0 0

View Code

原文链接: https://www.cnblogs.com/fengzy/archive/2013/06/01/3113039.html

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