棧的基本操作（C++）

棧的基本操作（C++）

1. #include<iostream>
2. #include<stdlib.h>
3. using namespace std;
4. template <class elemtype>
5. class stack {
6. public:
7. virtual bool is_empty() const = 0;
8. virtual void push(const elemtype &x) = 0;
9. virtual elemtype pop() = 0;
10. virtual elemtype top() const = 0;
11. virtual ~stack() {}
12. };
14. template <class elemtype>
15. class set_stack: public stack <elemtype> {
16. private:
17. elemtype *elem;
18. int top_p;
19. int max_size;
20. void double_space();
21. public:
22. set_stack(int init_size = 10) {
23. elem = new elemtype [init_size];
24. max_size = init_size;
25. top_p = -1;
26. }
27. ~set_stack() { delete[] elem; }
28. bool is_empty() const { return top_p == -1; }
29. void push(const elemtype &x) {
30. if(top_p == max_size - 1) {
31. double_space();
32. }
33. elem[++top_p] = x;
34. }
35. elemtype pop() {
36. return elem[--top_p];
37. }
38. elemtype top() const {
39. return elem[top_p];
40. }
41. };
43. template <class elemtype>
44. void set_stack<elemtype>::double_space(){
45. elemtype *tmp = elem;
46. elem = new elemtype[2*max_size];
47. for(int i = 0; i < max_size; ++i) {
48. elem[i] = tmp[i];
49. }
50. max_size *= 2;
51. delete[] tmp;
52. };
55. int main()
56. {
57. set_stack<int> *s = new set_stack<int>(10);
58. cout<<s->is_empty();
59. // s->push(3);
60. for(int i = 1; i <= 20; i++) {
61. s->push(i*10);
62. }
63. for(int i = 1; i <=20 ; i++) {
64. cout << s->top() << endl;
65. s->pop();
66. }
67. cout<<s->top();
68. return 0;
69. }
70. //這道題目的意義重大，標志我要全面學習C++了！呵呵，加油。