一段简单的练习代码，关于vector，queue，stack，priority

一段简单的练习代码，关于vector，queue，stack，priority_queue

代码：

  1 #include <assert.h>
  2 #include <vector>
  3 #include <queue>
  4 
  5 using namespace std;
  6 
  7 template <class T>
  8 class CStack{
  9 private:
 10     T* bottom;
 11     T* top;
 12     int size;
 13 public:
 14     CStack():top(bottom), bottom(new T[1]), size(1){}
 15     ~CStack(){
 16         if(!bottom)
 17             delete[] bottom;
 18     }
 19     bool empty()
 20     {
 21         return top == bottom;
 22     }
 23     bool full()
 24     {
 25         return (top - bottom) >= size;
 26     }
 27     void resize(int s)
 28     {
 29         T* tmp = bottom;
 30         bottom = new T[s];
 31         top = bottom + (top - tmp);
 32         memcpy(bottom, tmp, (size<s?size:s)*sizeof(T));
 33         size = s;
 34         delete[] tmp;
 35     }
 36     void push(T t)
 37     {
 38         if(full())
 39             resize(size*2);
 40         *top = t;
 41         top++;
 42     }
 43     void pop()
 44     {
 45         if(!empty())
 46             top--;
 47         else
 48             assert(false);
 49     }
 50     T peek()
 51     {
 52         if(!empty())
 53             return *(top-1);
 54         else
 55             assert(false);
 56         return T();
 57     }
 58 
 59 };
 60 
 61 
 62 
 63 int main()
 64 {
 65     CStack<int> stk;
 66     stk.push(1);
 67     stk.push(2);
 68     stk.push(3);
 69     stk.push(4);
 70     while(!stk.empty())
 71     {
 72         printf("%d
", stk.peek());
 73         stk.pop();
 74     }
 75 
 76     printf(">> 练习vector:
");
 77 
 78     vector<int> v;
 79     v.push_back(1);
 80     v.push_back(2);
 81     v.push_back(3);
 82     v.push_back(4);
 83     v.push_back(5);
 84     printf(">> 插入5个元素之后
");
 85     if(v.empty())
 86         printf("true == v.empty()
");
 87     printf("size:    	%d
", v.size());
 88     printf("capacity:	%d
", v.capacity());
 89     printf(">> 清空之后
");
 90     v.clear();
 91     if(v.empty())
 92         printf("true == v.empty()
");
 93     printf("size:    	%d
", v.size());
 94     printf("capacity:	%d
", v.capacity());
 95 
 96     // queue没有迭代器
 97     // queue只能访问队首元素
 98     // stack没有迭代器
 99     // stack只能访问栈顶元素
100     printf(">> 练习queue:
");
101     queue<int> q;
102     q.push(1);
103     q.push(2);
104     q.push(3);
105     q.push(4);
106     q.push(5);
107     q.pop();
108     q.pop();
109     if(!q.empty())
110         printf("%d 
", q.front());
111     q.pop();
112     if(!q.empty())
113         printf("%d 
", q.front());
114 
115     // heap是隐式表达，存在于algorithm中
116     // 函数有make_heap（将一段数据整理成堆）
117     // pop_heap（将堆顶放到队尾）
118     // push_heap（将尾元素放到堆顶并调整）
119     // sort_heap（堆排序算法）
120     // priority_queue基于heap实现
121     getchar();
122     return 0;
123 }

输出结果：

4
3
2
1
>> 练习vector:
>> 插入5个元素之后
size:           5
capacity:       6
>> 清空之后
true == v.empty()
size:           0
capacity:       6
>> 练习queue:
3
4