minStack实现

设计包含 min 函数的栈(栈)
定义栈的数据结构,要求添加一个 min 函数,能够得到栈的最小元素。
要求函数 min、push 以及 pop 的时间复杂度都是 O(1)。

 #include <algorithm>
 #include <iostream>
 #include <exception>
 #include <string>

 class illegalParameterValue
 {
     public:
         illegalParameterValue():errorMessage("Illegal parameter value"){}
         illegalParameterValue(const char* theMessage){ errorMessage = theMessage;}
         std::string errorMessage;
 };

 template<typename T>
 struct minStackElement{
     T element;
     T min;
 };

 template<typename T>
 class minStack{
 private:
     int top;
     int size;
     minStackElement<T>* arrayStack;
 public:
     minStack(int initCapacity)
     {
         try{
             if(initCapacity < )
                 throw illegalParameterValue("initCapacity must greater than 0");
         }catch(illegalParameterValue& e){
             std::cout << "initCapacity has been made to be 1" << std::endl;
             initCapacity = ;
         }
         arrayStack = new minStackElement<T>[initCapacity];
         size = initCapacity;
         top = -;
     }
     ~minStack()
     {
         delete [] arrayStack;
     }
     void push(T x)
     {
         minStackElement<T> e;
         e.element = x;
         if(top == -){
             e.min = x;
         }else if(x < arrayStack[top].min){
             e.min = x;
         }else{
             e.min = arrayStack[top].min;
         }
         if(top == size-)
         {
             minStackElement<T>* temp = arrayStack;
             arrayStack = new minStackElement<T>[*size];
             std::copy(temp,temp+size-,arrayStack);
             delete [] temp;
         }
         arrayStack[++top] = e;
     }

     void pop()
     {
         if(top == -)
             throw illegalParameterValue("the stack is empty");
         top--;
     }

     T min()
     {
         return arrayStack[top].min;
     }
 };