Hey guys I keep getting this error:

Thread 1: EXC_BAD_ACCESS (code=1, address=0x0)

When I call grid[x][y]->getType()

The first of these errors comes up on line 242 as shown here:

Note: If I try to replace this->grid[x[[y] with grid[x][y] it does not work either

My code is below, please help thanks!

#include

#include

#include

#include

#include

using namespace std;

class board;

class creature;

class ant;

class doodlebug;

//Indicates the integer that represents each creature

const int antInd= 1;

const int doodlebugInd = 2;

int ants = 0;

int doodlebugs = 0;

int empty=0;

class board {

friend class creature;

friend class ant;

friend class doodlebug;

public:

board(){};

creature* grid[20][20];

void createGrid();

void initialize(int& ants, int& doodlebugs, int& empty);

void simTurn();

void printGrid();

protected:

board* thisBoard;

};

class creature: public board {

friend class board;

public:

creature(): turnsWithoutFood(0), turnsSurvived(0){}

creature(board* boardptr,int x, int y) {};

creature(const creature &creatureTwo)

: x(creatureTwo.x), y(creatureTwo.y), turnsSurvived(creatureTwo.turnsSurvived), turnsWithoutFood(creatureTwo.turnsWithoutFood){};

creature &operator=(const creature & creatureTwo) {

x = creatureTwo.x;

y = creatureTwo.y;

turnsWithoutFood = creatureTwo.turnsWithoutFood;

turnsSurvived = creatureTwo.turnsSurvived;

return *this;

}

// virtual ~ creature();

void breed(int x, int y);

void starve(int x, int y);

// if(this->type==1)

// return 1;

// else {

// return 2;

// }

// };

private:

int type;

virtual int getType() = 0;

int x,y;

int turnsWithoutFood;

int turnsSurvived;

};

class ant: public creature {

friend class board;

public:

ant(): creature(), turnsSurvived(0){}

private:

int x,y;

ant(board* boardptr, int x,int y);

int getType() {

return 1;

}

int turnsWithoutFood;

int turnsSurvived;

int type=1;

void breed(int x, int y) ;

};

class doodlebug: public creature {

friend class board;

public:

doodlebug(): creature(), turnsWithoutFood(0), turnsSurvived(0){}

private:

int turnsWithoutFood;

int turnsSurvived;

int type=2;

doodlebug(board* boardptr, int x, int y) {};

int getType() {

return 2;

}

void breed(int x, int y);

void starve(int x, int y);

void eat() ;

};

void board::createGrid() {

srand(time(NULL));

for(int i=0;i

for(int j=0;j

grid[i][j]= NULL;

}

}

}

void board::initialize(int& ants, int& doodlebugs, int& empty) {

this->createGrid();

while(doodlebugs

int x = rand()%20;

int y= rand()%20;

// creature* thisCreature = grid[x][y];

if(grid[x][y] == NULL)

// delete thisCreature;

grid[x][y] = new doodlebug(this,x,y);

doodlebugs++;

}

while(ants

int x = rand()%20;

int y= rand()%20;

// creature* thisCreature = grid[x][y];

if(grid[x][y] == NULL) {

// delete thisCreature;

grid[x][y] = new ant(this,x,y);

ants++;

}

}

}

void board::printGrid() {

for(int i=0;i

cout

for(int j=0;j

if(grid[i][j] == NULL) {

cout

}

else if(grid[i][j]->getType() == 2) {

cout

}

else {

cout

}

}

}

cout

}

ant::ant(board*, int, int)

{

/othing

}

void ant::breed( int x, int y) {

if(grid[x+1][y] == NULL) {

grid[x+1][y] = new ant(this,x+1,y);

ant *thisAnt = (ant *)grid[x+1][y];

thisAnt->turnsSurvived=0;

ants++;

}

else if(grid[x-1][y] == NULL) {

grid[x-1][y] = new ant(this,x-1,y);

ants++;

ant *thisAnt = (ant *)grid[x-1][y];

thisAnt->turnsSurvived=0;

}

else if(grid[x][y+1] == NULL) {

grid[x][y+1] = new ant(this,x,y+1);

ants++;

ant * thisAnt = (ant *)grid[x][y+1];

thisAnt->turnsSurvived=0;

}

else if(grid[x][y-1] == NULL) {

grid[x][y-1] = new ant(this,x,y-1);

ants++;

ant * thisAnt = (ant *)grid[x][y-1];

thisAnt->turnsSurvived=0;

}

}

void doodlebug::breed(int x, int y) {

if(grid[x+1][y]==NULL) {

grid[x+1][y] = new doodlebug(this,x+1,y);

doodlebugs++;

doodlebug* thisDoodlebug = (doodlebug *)grid[x+1][y];

thisDoodlebug->turnsSurvived=0;

thisDoodlebug->turnsWithoutFood=0;

}

else if(grid[x-1][y]==NULL) {

grid[x-1][y] = new doodlebug(this,x-1,y);

doodlebugs++;

doodlebug* thisDoodlebug = (doodlebug *)grid[x-1][y];

thisDoodlebug->turnsSurvived=0;

thisDoodlebug->turnsWithoutFood=0;

}

else if(grid[x][y+1] == NULL) {

grid[x][y+1] = new doodlebug(this,x,y+1);

doodlebugs++;

doodlebug* thisDoodlebug = (doodlebug *)grid[x][y+1];

thisDoodlebug->turnsSurvived=0;

thisDoodlebug->turnsWithoutFood=0;

}

else if(grid[x][y-1]== NULL) {

grid[x][y+1] = new doodlebug(this,x,y-1);

doodlebugs++;

doodlebug* thisDoodlebug = (doodlebug *)grid[x][y-1];

thisDoodlebug->turnsSurvived=0;

thisDoodlebug->turnsWithoutFood=0;

}

}

void doodlebug::starve(int x, int y) {

delete this;

doodlebugs--;

empty++;

}

void board::simTurn() {

int counter=0;

int right = 1;

int left = 2;

int up = 3;

int down = 4;

int x = 0;

int y = 0;

while(counter

if((this->grid[x][y])->getType() == antInd) {

ant* thisAnt = (ant* )grid[x][y];

int dir = rand()%4;

if(x==0) {

if(dir==2) {

dir=1;

}

}

if(y==0) {

if(dir==4) {

dir=3;

}

}

if(x==19) {

if(dir==1) {

dir=2;

}

}

if(y==19) {

if(dir==3) {

dir=4;

}

}

if(thisAnt->turnsSurvived==3) {

thisAnt->breed(x,y);

}

if(dir==right) {

if(grid[x+1][y] == NULL) {

// thisAnt = (ant*)grid[x+1][y];

// thisAnt->x+=1;

grid[x+1][y] = thisAnt;

ant* newAnt= thisAnt;

delete thisAnt;

newAnt->turnsSurvived++;

}

else if(grid[x+1][y]->getType() == doodlebugInd){

delete thisAnt;

//ant is eaten

ants--;

thisAnt->turnsSurvived=0;

}

else {

thisAnt->turnsSurvived++;

}

}

if(dir==left) {

if(grid[x-1][y] == NULL) {

// thisAnt = (ant*)grid[x-1][y];

// thisAnt->x-=1;

// delete grid[x][y];

// thisAnt->turnsSurvived++;

// thisAnt = (ant*)grid[x+1][y];

// thisAnt->x+=1;

grid[x-1][y] = thisAnt;

ant* newAnt= thisAnt;

delete thisAnt;

newAnt->turnsSurvived++;

}

else if(grid[x-1][y]->getType() == doodlebugInd){

delete thisAnt;

//ant is eaten

ants--;

thisAnt->turnsSurvived=0;

}

else {

thisAnt->turnsSurvived++;

}

}

if(dir==up) {

if(grid[x][y+1] == NULL) {

// thisAnt = (ant*)grid[x][y+1];

// thisAnt->y+=1;

// delete grid[x][y];

// thisAnt->turnsSurvived++;

// thisAnt = (ant*)grid[x+1][y];

// thisAnt->x+=1;

grid[x][y+1] = thisAnt;

ant* newAnt= thisAnt;

delete thisAnt;

newAnt->turnsSurvived++;

}

else if(grid[x][y+1]->getType() == doodlebugInd){

delete thisAnt;

//ant is eaten

ants--;

thisAnt->turnsSurvived=0;

}

else {

thisAnt->turnsSurvived++;

}

}

if(dir==down) {

if(grid[x][y-1] == NULL) {

// thisAnt = (ant*)grid[x][y-1];

// thisAnt->y-=1;

// delete grid[x][y];

// thisAnt->turnsSurvived++;

// thisAnt = (ant*)grid[x+1][y];

// thisAnt->x+=1;

grid[x][y-1] = thisAnt;

ant* newAnt= thisAnt;

delete thisAnt;

newAnt->turnsSurvived++;

}

else if(grid[x][y-1]->getType() == doodlebugInd){

delete thisAnt;

//ant is eaten

ants--;

thisAnt->turnsSurvived=0;

}

else {

thisAnt->turnsSurvived++;

}

}

// }

if(x==19) {

y++;

}

else {

x++;

}

counter++;

}

else if(grid[x][y]->getType() == doodlebugInd) {

doodlebug* thisDoodlebug = (doodlebug *)grid[x][y];

if(thisDoodlebug->turnsSurvived==8) {

thisDoodlebug->breed(x,y);

}

if(thisDoodlebug->turnsWithoutFood==3) {

thisDoodlebug->starve(x,y);

}

int dir = rand()%4;

if(x==0) {

if(dir==2) {

dir=1;

}

}

if(y==0) {

if(dir==4) {

dir=3;

}

}

if(x==19) {

if(dir==1) {

dir=2;

}

}

if(y==19) {

if(dir==3) {

dir=4;

}

}

if(dir==right) {

if(grid[x+1][y]== NULL) {

// thisDoodlebug = (doodlebug *)grid[x][y];

// thisDoodlebug->x+=1;

// delete grid[x][y];

// thisDoodlebug->turnsWithoutFood++;

// thisDoodlebug->turnsSurvived++;

grid[x+1][y] = thisDoodlebug;

doodlebug* newDoodlebug= thisDoodlebug;

delete thisDoodlebug;

newDoodlebug->turnsSurvived++;

newDoodlebug->turnsWithoutFood++;

}

else if(grid[x+1][y]->getType() == antInd) {

thisDoodlebug->turnsWithoutFood=0;

thisDoodlebug->turnsSurvived++;

}

else {

//do nothing

thisDoodlebug->turnsWithoutFood++;

thisDoodlebug->turnsSurvived++;

}

}

else if(dir==left) {

if(grid[x-1][y]== NULL) {

// thisDoodlebug = (doodlebug *)grid[x][y];

// thisDoodlebug->x-=1;

// delete grid[x][y];

// thisDoodlebug->turnsWithoutFood++;

// thisDoodlebug->turnsSurvived++;

grid[x-1][y] = thisDoodlebug;

doodlebug* newDoodlebug= thisDoodlebug;

delete thisDoodlebug;

newDoodlebug->turnsSurvived++;

newDoodlebug->turnsWithoutFood++;

}

else if(grid[x-1][y]->getType() == antInd) {

thisDoodlebug->turnsWithoutFood=0;

thisDoodlebug->turnsSurvived++;

}

else {

//do nothing

thisDoodlebug->turnsWithoutFood++;

thisDoodlebug->turnsSurvived++;

}

}

else if(dir==up) {

if(grid[x][y+1]== NULL) {

// thisDoodlebug = (doodlebug *)grid[x][y];

// thisDoodlebug->y+=1;

// delete grid[x][y];

// thisDoodlebug->turnsWithoutFood++;

// thisDoodlebug->turnsSurvived++;

grid[x][y+1] = thisDoodlebug;

doodlebug* newDoodlebug= thisDoodlebug;

delete thisDoodlebug;

newDoodlebug->turnsSurvived++;

newDoodlebug->turnsWithoutFood++;

}

else if(grid[x][y+1]->getType() == antInd) {

thisDoodlebug->turnsWithoutFood=0;

thisDoodlebug->turnsSurvived++;

}

else {

//do nothing

thisDoodlebug->turnsWithoutFood++;

thisDoodlebug->turnsSurvived++;

}

}

if(dir==down) {

if(grid[x][y-1]== NULL) {

// thisDoodlebug = (doodlebug *)grid[x][y];

// thisDoodlebug->y-=1;

// delete grid[x][y];

// thisDoodlebug->turnsWithoutFood++;

// thisDoodlebug->turnsSurvived++;

grid[x][y-1] = thisDoodlebug;

doodlebug* newDoodlebug= thisDoodlebug;

delete thisDoodlebug;

newDoodlebug->turnsSurvived++;

newDoodlebug->turnsWithoutFood++;

}

else if(grid[x][y-1]->getType() == antInd) {

thisDoodlebug->turnsWithoutFood=0;

thisDoodlebug->turnsSurvived++;

}

else {

//do nothing

thisDoodlebug->turnsWithoutFood++;

thisDoodlebug->turnsSurvived++;

}

}

if(x==19) {

y++;

}

else {

x++;

}

counter++;

}

}

}

int main() {

srand(time(NULL));

board Board;

Board.initialize(ants,doodlebugs,empty);

Board.printGrid();

bool gameOver = false;

while(gameOver==false) {

cout

string key;

cin>>key;

if(key=="enter") {

Board.simTurn();

Board.printGrid();

}

else if(key=="stop") {

gameOver=true;

}

}

}

88hw)main.cpp) M board:simTurn intxe int y- while (countergridlx]Iy])->getType)antInd) Thread 1: EXC_BAD_ACCE. ant* thisAnt-(ant* )grid[x][y]; int dir- rand ()964 ; if (x0) { if(dir:#2 ) dir-1; if(y 0) if(dir4) 1 dir-3; if(x--19) if(dir--1) ( dir-2