C++ Passing class Object to function - c++

Question

I'm new to C++ programming.
Now I have the state class. I want to create neighboring states with this class, so I add the function getNeighboringStates() to my class. In this function I pass in "neighboring_states" to function set_neighboring_state(), this function change "neighboring_states"'s value.
In this function, I set a for loop to test. It print out "7 1 0 3 6 4 5 2 8", which is the value I want. But In the function getNeighboringStates(), I also set a for loop that has the same mission as in set_neighboring_state(), but the screen display "0 1 4716672 2686652 2686528 0 4716676 4519501 4716676".
I don't know what's wrong with my code. What do I need to do now?
int n; // The number of columns as well as rows of the board
int k; // The kind of heuristic function to use
int tilesCount; // The number of tiles, including the blank one
int statesCount; // The number of states generated
int* m_initTiles;
int* m_goalTiles;
int tmpTile;
const int UP = 0;
const int DOWN = 1;
const int RIGHT = 2;
const int LEFT = 3;
int* direction;
class State {
public:
State(){}
int getBlankTilePosition() {
for (int i = 0; i < n * n; i++) {
if (stateTiles[i] == 0)
return i;
}
}
void set_neighboring_state(State* neighboring_state, int direction) {
int blankPosition = getBlankTilePosition();
int neighbor_tiles[n * n];
for (int i = 0; i < n * n; i++) {
neighbor_tiles[i] = getStateTiles()[i];
}
switch(direction) {
case UP:
if (blankPosition/n < 1) return;
else {
swap(neighbor_tiles[blankPosition], neighbor_tiles[blankPosition - n]);
neighboring_state->set_tiles(neighbor_tiles);
// This for loop print out "7 1 0 3 6 4 5 2 8"
for (int i = 0; i < n * n; i++)
cout << neighboring_state.getStateTiles()[i] << " "; cout << endl;
}
break;
case DOWN:
if (blankPosition/n == n - 1) return;
else {
swap(neighbor_tiles[blankPosition], neighbor_tiles[blankPosition + n]);
neighboring_state->set_tiles(neighbor_tiles);
}
break;
case LEFT:
if (blankPosition % n == 0) return;
else {
swap(neighbor_tiles[blankPosition], neighbor_tiles[blankPosition - 1]);
neighboring_state->set_tiles(neighbor_tiles);
}
break;
default:
if ((blankPosition + 1) % n == 0) return;
else {
swap(neighbor_tiles[blankPosition], neighbor_tiles[blankPosition + 1]);
neighboring_state->set_tiles(neighbor_tiles);
}
break;
}
}
/*
The maximum number of neighboring state that can be created is 4.
This function return the neighboring states of a certain state.
The first state represents for the "left" neighbor, the second,
the third and the fourth represent the "right", "up, and "down"
neighbor, respectively.
*/
State* getNeighboringStates() {
State* neighboring_states;
neighboring_states = new State[4];
for (int i = 0; i < 4; i++)
set_neighboring_state(&neighboring_states[i], direction[i]);
// This print out "0 1 4716672 2686652 2686528 0 4716676 4519501 4716676"
cout << endl;
for (int i = 0; i < n * n; i++)
cout << neighboring_states[0].getStateTiles()[i] << " ";
cout << endl;
return neighboring_states;
}
State(int* pStateTiles) {
stateTiles = pStateTiles;
}
void set_tiles(int* tiles) {
stateTiles = tiles;
}
int* getStateTiles() {
return stateTiles;
}
private:
int* stateTiles;
};
void input(const char* fileName) {
ifstream fin;
fin.open(fileName);
// read n, k from file
fin >> n >> k;
// allocate m_initTiles and m_goalTiles memory
m_initTiles = new int[n * n];
m_goalTiles = new int[n * n];
for (int i = 0; i < n * n; i++)
fin >> m_initTiles[i];
for (int i = 0; i < n * n; i++)
fin >> m_goalTiles[i];
for (int i = 0; i < n * n; i++)
cout << m_initTiles[i] << " ";
cout << endl;
for (int i = 0; i < n * n; i++)
cout << m_goalTiles[i] << " ";
cout << endl;
fin.close();
}
void initDirection() {
direction = new int[4];
direction[0] = UP;
direction[1] = DOWN;
direction[2] = RIGHT;
direction[3] = LEFT;
}
int main() {
input("nPuzzle.inp");
initDirection();
State init_state (m_initTiles);
State goal_state (m_goalTiles);
State* init_neighbor = init_state.getNeighboringStates();
// int* state_tile = init_neighbor[0].getStateTiles();
// for (int i = 0; i < n * n; i++)
// cout << state_tile[i] << " ";
return 0;
}

Answer 1

int blankPosition = getBlankTilePosition();
int neighbor_tiles[n * n];
Remove int neighbor_tiles[n * n]; line from above code segment and make it global available to all function , so declare it as data of a class not for function i.e. add int neighbor_tiles[n * n]; to class as an data type .