why the player is not switching between "X" and "O"?

[philip1999]

I cannot understand why the player is not switching between "X" and "O"?

  #include<stdio.h>
#include<iostream>
using namespace std;

char matrix[3][3] = { '.','.','.','.','.','.','.','.','.' };
char player = 'X';

void display()
{
	for (int i = 0; i < 3; i++)
	{
		for (int j = 0; j < 3; j++)

		{
			cout << matrix[i][j] << " ";
		}
		cout << endl;
	}
}

void togglePlayer(char player)
{
	if (player=='O')
	{
		player = 'X';
	}
	else player = 'X';
}

void input()
{
	int num;
	cout << "Enter the desired matrix" << endl;
	cin >> num;
	if (num == 1)
	{
		matrix[0][0] = player;
	}
	else if (num == 2)
	{
		matrix[0][1] = player;
	}
	else if (num == 3)
	{
		matrix[0][2] = player;
	}
	else if (num == 4)
	{
		matrix[1][0] = player;
	}
	else if (num == 5)
	{
		matrix[1][1] = player;
	}
	else if (num == 6)
	{
		matrix[1][2] = player;
	}
	else if (num == 7)
	{
		matrix[2][0] = player;
	}
	else if (num == 8)
	{
		matrix[2][1] = player;
	}
	else if (num == 9)
	{
		matrix[2][2] = player;
	}

}

int main()
{
	while (true)
	{
		display();
		togglePlayer(player);
		input();
	}
	system("pause");
	return 0;
}

[E0p9LyTq]

why the player is not switching between "X" and "O"?

Look closely at your togglePlayer() function. You are setting player to 'X' no matter what.

Try:

void togglePlayer(char player)
{
	if (player=='O')
	{
		player = 'X';
	}
	else player = 'O';
}

[mbozzi]

Don't forget to pass `player' by reference

void togglePlayer(char &player) 
{
  // ...
}

[philip1999]

@FurryGuy Even though I tried your function, it is still the same (not switching between "X" and "O")

[lastchance]

@philip1999,
Please read @mbozzi's post. You need that ampersand & in the parameter list of the function definition. Otherwise player will be passed by value: i.e. only a copy goes to your function and nothing goes back. I appreciate that this may be different from some other programming languages.