How to write code to show who has won the game - visual-c++

Question

i have made a cannon shooting game for two player, the aim is to break the castle down and then try to land the cannon ball onto the opponent but the problem is idk how to write code to show who has won the game when the game is over and all i know is that the code will need to written in the game over section & I am new to code as well
void CMyGame::OnUpdate()
{
if (m_mode == MODE_SHOOT)
{
/////////////////////////////////////////////////
// this code will only be executed while shooting
// TODO: 1. Add the gravitation
m_ball.Accelerate(0, -8);
// TODO: 2. Check if cannon hit? game over?
if (m_ball.HitTest(m_cannons[1 - m_turn]))
{
GameOver();
}
// TODO: 3. Check if the ball is outside the screen. Test the following cases:
// - ball to the left of the screen
if (m_ball.GetX() < 0)
NextTurn();
// - ball to the right of the screen (screen width = 800)
if (m_ball.GetX() > 800)
NextTurn();
// - ball below the screen
if (m_ball.GetY() < 0)
NextTurn();
// TODO: 4. Check if the ball hit the castle?
for each (CSprite * pSprite in m_castle)
{
if (m_ball.HitTest(pSprite))
NextTurn();
}
}
// Check if the castle has taken damage
for (CSprite* pSprite : m_castle)
{
if (m_ball.HitTest(pSprite))
pSprite->Delete();
}
m_castle.delete_if(deleted);
// Update the ball's position
m_ball.Update(GetTime());
the part i need help on is how to write code that will show who has won the game
// called when Game is Over
void CMyGame::OnGameOver()
{
m_cannons[1 - m_turn]->SetImage("fire");
m_mode = MODE_GAMEOVER;
}

Answer 1

Hard to say without seeing the rest of your code and info on how your game works, but you can follow something like this:
Assuming you can check when a cannon lands somewhere and can track the % hit points of each player (which I believe you can do considering you have gravity planned in your given code):
Write a function which is called each time a cannon ball lands, check if the ball has dealt the final blow on the opponent's character. From what you say, you probably do not need to do this check until the castle has been broken down. So something along the lines of if(!castleBroken) {return;} at the start of the function would only check the opponent's HP if the castle is broken (again, assuming that the opponent can only take damage if the castle is broken). Here, castleBroken is a bool which starts as false and becomes true when the cannon has broken the opponent's castle.
This is a similar idea to a Tic-Tac-Toe game I wrote in the past, where after each move, I would check the board state. If the game was over, the game over screen would be printed with the winner declared, or in some cases, a draw.