[C++][windows]C++类成员函数默认参数和成员变量初始化问题

#pragma once
#include<iostream>


class TestManager
{
public:
	int a = 0;
	float b = 1;
	double c = 2;
	char* d = (char*)"123";
	int Add(int a , int b);
};


struct ModeType
{
	int RTX30 = 1;
	int GTX660 = 2;
};

#include "TestManager.h"

int TestManager::Add(int a, int b)
{
	return a + b;
}

#include "TestManager.h"
int main()
{
	TestManager tm;
	std::cout << tm.b << "\n";
	int c = tm.Add(2);
	std::cout << c << "\n";
	getchar();
}