C ++ application stack _ the nearest match

#include <iostream>
using namespace std;
#define MAX_SIZE 1024
class Stack
{
public:
	Stack();
	~Stack();
	void push_back(void*);
	void* Front();
	void pop_front();
	int  GetSize();
	void Clear();
	bool empty();
private:
	void* data[1024];
	int size;
};	
Stack::Stack()
{
	for (int i = 0; i < MAX_SIZE ; i++)
	{
		data[i] = NULL;
	}
	size = 0;
}
Stack::~Stack()
{
	if (this->data)
	{
		//delete []this->data;
		this->size = 0;
	}
}
void Stack::push_back(void*data){
	if (data==NULL)
	{
		return;
	}
	this->data[this->size] = data;
	++this->size;
};
void*Stack:: Front()   {
	if (this->size==0)
	{
		return NULL;
	}
	return this->data[this->size - 1];
};
void Stack::pop_front(){
	if (this->size == 0)
	{
		return;
	}
	this->data[this->size - 1] = NULL;
	--this->size;
};
int  Stack::GetSize()  {
	return this->size;
};
void Stack::Clear()    {
	if (this->size == 0)
	{
		return;
	}
	for (int i = 0; i < this->size; i++)
	{
		this->data[i] = NULL;
	}
	this->size = 0;
};
bool Stack::empty() {
	if (this->size==0)
	{
		return true;
	}
	return false;
}
class Compare {
public:
	char str;
	int index;
};
bool CompareLeft(char str) {
	if (str=='(')
	{
		return true;
	}
	return false;
}
bool CompareRight(char str) {
	if (str == ')')
	{
		return true;
	}
	return false;
}
void PrintCpmpare(char*str, int index) {
	cout << str << endl;
	for (int i = 0; i < index; i++)
	{
		cout << " ";
	}
	cout << "↑" << endl;
}
int main() {
	Stack stack;
	char*str = "((6+1*5))+(5+6(6*3)";
	char*str2 = str;
	//遇左括号进栈，遇右括号出栈，判断是否是左括号，是配对成功，否失败，

	int index = 0;
	while (*str2 !='\0')
	{
		if (CompareLeft(*str2))
		{
			Compare*a = new Compare;
			a->str = *str2;
			a->index = index;
			stack.push_back(a);
		}
		if (CompareRight(*str2))
		{
			if (stack.GetSize()==0)
			{
				PrintCpmpare(str, index);
				break;
			}
			Compare* s = (Compare*)stack.Front();
			if (CompareLeft(s->str))
			{
				stack.pop_front();
				delete s;
			}
		}
		++str2;
		++index;
	}
	int x = stack.GetSize();
	for (int i = 0; i < x; i++)
	{
		Compare* s = (Compare*)stack.Front();
		PrintCpmpare(str, s->index);
		stack.pop_front();
		delete s;
	}
	return 0;
}

Renderings: