使用面向过程的方法：

#include <iostream>

using namespace std;

class Cube{
	private:
		int m_a;
		int m_b;
		int m_c;
		
	public:
		//设置立方体的长宽高
		void setABC(int a, int b, int c){
			m_a = a;
			m_b = b;
			m_c = c;
		}
	
		int getA() {
			return m_a;
		}
	
		int getB() {
			return m_b;
		}
	
		int getC() {
			return m_c;
		}
};


//判断两个立方体是否相等
bool judge(Cube& c1, Cube& c2)
{
	if (c1.getA() == c2.getA() &&
		c1.getB() == c2.getB() &&
		c1.getC() == c2.getC()) {
		return true;
	}
	else {
		return false;
	}
}

int main(void){
	Cube c1;
	c1.setABC(10, 20, 30);

	Cube c2;
	c2.setABC(10, 20, 30);

	// 面向过程的判断方法
	if (judge(c1, c2) == true) {
		cout << "相同" << endl;
	}
	else {
		cout << "不同" << endl;
	}
}

使用面向对象的方法：

#include <iostream>

using namespace std;

class Cube{
	private:
		int m_a;
		int m_b;
		int m_c;
	
	public:
		//设置立方体的长宽高
		void setABC(int a, int b, int c)
		{
			m_a = a;
			m_b = b;
			m_c = c;
		}
	
		int getA() {
			return m_a;
		}
	
		int getB() {
			return m_b;
		}
	
		int getC() {
			return m_c;
		}
	
		//提供一个判断两个立方体是否相等的成员函数
		bool judge(Cube& another_c){
			if (m_a == another_c.m_a &&   // 同类之间无私处
				m_b == another_c.getB() &&
				m_c == another_c.getC()) {
				return true;
			} else {
				return false;
			}
		}
};


int main(void){
	Cube c1;
	c1.setABC(10, 20, 30);

	Cube c2;
	c2.setABC(10, 20, 30);

	//面向对象的判断方法
	if (c1.judge(c2) == true) {
		cout << "相同" << endl;
	}
	else {
		cout << "不同" << endl;
	}
}