栈的C++实现（数组）——创建-push-pop-top-清空栈-处理栈

今天学习了利用数组方式的栈的C++实现，这种方式跟指针实现有很多不一样的地方：

栈的指针实现，栈的创建申请头结点，push需要申请新的结点，pop释放结点，这些结点都放在第一个位置，top时，S->next->data即可。

栈的数组实现，只申请一个结点，该结点的结构体内包含，数组的最大容量、栈顶元素下标、指向整形数组的指针（用于存放和删除新的元素）。

S->topOfStack == -1,空栈；

S->topOfStack == S->capacity - 1,满栈；

1、声明结点

1     struct Node
2     {
3         int capacity;    //数组的最大容量
4         int topOfStack;  //栈顶为-1表示空栈，栈顶元素下标，每次添加新的元素，栈顶元素下标加1
5         int *Array;         //指向整形数组的指针
6     };
7     typedef struct Node stack;

2、空栈，满栈判断

1 int stackArray::isEmpty(stack *S)
2 {
3     return S->topOfStack == emptyTOS;
4 }
5 int stackArray::isFull(stack *S)
6 {
7     return S->topOfStack == S->capacity - 1;
8 }

3、创建栈

 1 stackArray::stack *stackArray::createStack(int maxElements)
 2 {
 3     if (maxElements < minStackSize)
 4         cout << "the space of stack is too short,please increase value of maxElements!" << endl;
 5
 6     stack *S;
 7     S = (stack*)new(stack);
 8     if (S == NULL)
 9         cout << "Out of space! " << ‘\n‘;
10
11     S->Array = new int[maxElements];
12     if (S->Array == NULL)
13         cout << "Out of space! " << ‘\n‘;
14
15     S->topOfStack = emptyTOS;
16     makeEmpty(S);
17     return S;
18 }

4、清空，处理栈

 1 void stackArray::makeEmpty(stack *S)
 2 {
 3     if (S->topOfStack == emptyTOS)
 4         cout << "Donnot need to empty stack! " << ‘\n‘;
 5     else
 6         S->topOfStack = emptyTOS;    //栈顶元素置-1，表示空栈
 7 }
 8
 9 void stackArray::disposeStack(stack *S)
10 {
11     while (S != NULL)
12     {
13         free(S->Array);  //释放数组首地址即可
14         free(S);
15     }
16 }

5、push,top,pop

 1 stackArray::stack *stackArray::push(stack *S)
 2 {
 3     if (isFull(S))
 4     {
 5         cout << "stack is full!" << endl;
 6         return 0;
 7     }
 8     int x = 0;
 9     cout << "Please input the data to push: " << endl;
10     scanf_s("%d", &x);
11     S->Array[++S->topOfStack] = x;
12     return S;
13 }
14 int stackArray::top(stack *S)
15 {
16     if (isEmpty(S))        //非空判断
17     {
18         cout << "empty stack! " << endl;
19         return -1;
20     }
21     else
22         return S->Array[S->topOfStack];
23 }
24 stackArray::stack *stackArray::pop(stack *S)
25 {
26     if (isEmpty(S))        //非空判断
27     {
28         cout << "empty stack! " << endl;
29         return 0;
30     }
31     else
32     {
33         S->topOfStack--;
34         return S;
35     }
36 }

6、主函数

 1 int main(int argc, char * argv[])
 2 {
 3     cout << ‘\n‘ << "***************************************" << ‘\n‘ << ‘\n‘;
 4     cout << "Welcome to the stackArray world! " << ‘\n‘;
 5     cout << ‘\n‘ << "***************************************" << ‘\n‘ << ‘\n‘;
 6
 7     int i = 1;
 8     int j = 0;
 9     int topElement = 0;
10     stackArray *a = new stackArray;
11     stackArray::stack *S = NULL;
12     //int x = 0;
13     while (i)
14     {
15         cout << ‘\n‘ << "***************************************" << ‘\n‘;
16         cout << " 0 : end the stack " << ‘\n‘;
17         cout << " 1 : creat a stack " << ‘\n‘;
18         cout << " 2 : display the top element of stack  " << ‘\n‘;
19         cout << " 3 : push a node in the stack  " << ‘\n‘;
20         cout << " 4 : pop a node from the stack  " << ‘\n‘;
21         cout << "***************************************" << ‘\n‘;
22         cout << "Please input the function your want with the number above : " << ‘\n‘;
23         scanf_s("%d", &j);
24
25         switch (j)
26         {
27         case 1:
28             cout << "CreatStack now begin : ";
29             S = a->createStack(5);
30             break;
31         case 2:
32             topElement = a->top(S);
33             cout << "The top element of stack is : " << topElement;
34             break;
35         case 3:
36             cout << "push now begin : ";
37             S = a->push(S);
38             break;
39         case 4:
40             cout << "pop now begin : ";
41             S = a->pop(S);
42             break;
43         default:
44             cout << "End the stack. ";
45             a->disposeStack(S);
46             i = 0;
47             break;
48         }
49
50     }
51
52     return 0;
53 }

效果展示