C++

4. Write a stack class using an array (from the heap) to implement it. What is a "stack"? We saw the run-time stack in class. It is a data structure that allows us to "push" an element to the "top", to "pop" from the "top". In fact, for the no-recursive towers, we used a vector as a stack. class stack\} private: int top; // top is the index into the array for the current top int * p;//p is a pointer into the heap where the stack is actually //located. Just like for SA class. int size; // size of the array allocated for the stack public: stack(); // a stack to hold 100 stack(int n ) // a stack to hold n elements rstack(); bool empty(); void push( int );// don't forget to test if stack is full int pop();// return and remove the "top" element of the stack. // don't forget to test if the stack is empty Test it with the following main function: int main()\{ stack s(10); s.push(1); s.push(2); s.push(3); for ( i=0;i