Multidimensional array not changing elements from function for some reason - c++

Question

The function player_attack() changes the elements of the multi-dimensional array pc_board but when i reprint it in main, the array prints unchanged.
I removed all unnecessary code.
I tried to pass is at as a parameter to the function but i got an error for using a multidimensional array in the parameter.
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bool game_won = false;
string board[5][5];
string pc_board[5][5];
void initialize_player_board() {
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
board[i][j] = "-";
}
}
}
void print_map() {
for (int i = 0; i < 5; i++) {
cout << setw(5);
cout << i << setw(5);
for (int j = 0; j < 5; j++) {
cout << board[i][j] << setw(5);
}
cout << setw(10);
for (int j = 0; j < 5; j++) {
cout << pc_board[i][j] << setw(5);
}
cout << endl;
}
}
void pc_add_battleship() {
int x = 0;
int y = 0;
int choice_generator = 0;
char choice;
x = rand() % 4 + 1;
y = rand() % 4 + 1;
choice_generator = rand() % 2;
if (choice_generator == 0) {
choice = 'h';
}
else {
choice = 'v';
}
if (choice == 'h') {
pc_board[y - 1][x] = 'O';
pc_board[y][x] = 'O';
pc_board[y + 1][x] = 'O';
}
if (choice == 'v') {
pc_board[y][x - 1] = 'O';
pc_board[y][x] = 'O';
pc_board[y][x + 1] = 'O';
}
}
void player_attack() {
int x = 0;
int y = 0;
cout << "Choose an x coordinate to attack: " << endl;
cin >> x;
cout << "Choose a y coordinate to attack: " << endl;
cin >> y;
if (pc_board[y][x] == "O") {
cout << "HIT!" << endl;
pc_board[y][x] == "H";
}
else {
cout << "Miss." << endl;
pc_board[y][x] == "M";
}
}
int main()
{
srand(time(0));
initialize_player_board();
initialize_pc_board();
cout << "Welcome to the battleship game." << endl;
print_map();
Add_battleship();
pc_add_battleship();
while (!game_won) {
print_map();
player_attack();
}
return 0;
}
$
I expected for the multidimensional array to change its elements due to the function

Answer 1

In your function player_attack you use wrong operator:
if (pc_board[y][x] == "O") {
cout << "HIT!" << endl;
pc_board[y][x] == "H"; // here
}
else {
cout << "Miss." << endl;
pc_board[y][x] == "M"; // and here
}
instead of == that is a comparison operator you should use = that is the assignment operator.
Using operator == in this context is still valid C++ syntax, which produces a boolean value, however it does not modify the arguments (which are left and right side of comparison), which is probably what you want to do in most cases. Enabling compiler flags like -Wall or Wextra along with Werror helps to avoid this kind of bugs.