Fun snake game with singly linked list

snake.cpp

//copyright kevin nicky setiawan
#include <stdio.h>
#include <malloc.h>
#include <Windows.h>
#include <ctype.h>
#include <conio.h>
#include <time.h>
#define ff fflush(stdin)
struct Body{
	int x;
	int y;

	Body *next;
}*head, *tail;

int map[40][120];

int sizeX = 90;
int sizeY = 20;
int score = 0;
int xFood = 4;
int yFood = 10;

void createBody(int x, int y){
	Body *body = (Body *) malloc (sizeof(Body));
	body->x = x;
	body->y = y;
	if (!head){
		head = tail = body;
	}
	else{
		tail->next = body;
		//body->prev = tail;
		tail = body;
	}
	tail->next = NULL;
}

void gotoxy(int x, int y){
	COORD c = {x, y};
	SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), c);
}

void createMap(){
	for (int i = 0; i < sizeY; i++){
		for (int j = 0; j < sizeX; j++){
			if (i == 0 || i == sizeY - 1 || j == 0 || j == sizeX - 1) map[i][j] = 1;
			else map[i][j] = 0;
		}
	}
	map[yFood][xFood] = 3;
}

void createFood(){
	srand(time(NULL));
	map[yFood][xFood] = 0;
	do{
		xFood = rand() % (sizeX - 1) + 1;
		yFood = rand() % (sizeY - 1) + 1;
	} while (map[yFood][xFood] != 0);
	map[yFood][xFood] = 3;
	gotoxy(xFood, yFood);
	printf("*");
}

void viewMap(){
	for (int i = 0; i < sizeY; i++){
		for (int j = 0; j < sizeX; j++){
			if (map[i][j] == 1) printf("%c", 177);
			else if (map[i][j] == 3) printf("*");
			else printf(" ");
		}
		puts("");
	}
}

bool run(int x, int y){
	Body *curr = head;
	int tempX;
	int tempY;
	int helpX;
	int helpY;
	while (curr){		
		if (curr == head){
			if(score>2){
				Body *vcurr=head->next->next;
				while(vcurr){
					if(vcurr->x == head->x && vcurr->y == head->y ){
					return false;
					}
					vcurr=vcurr->next;
				}
			}
			
			map[curr->y][curr->x] = 0;
			if(head->x + x < 1 || head->x + x > sizeX - 2 || head->y + y < 1 || head->y + y > sizeY - 2){
				return false;
			}
			if (head->x == xFood && head->y == yFood){
				int newX = tail->x - x;
				int newY = tail->y - y;
				createBody(newX, newY);
				score++;
				createFood();
			}

			gotoxy(curr->x, curr->y);
			printf(" ");
			tempX = curr->x;
			tempY = curr->y;
			curr->x = curr->x + x;
			curr->y = curr->y + y;		
		} else{
			
			map[curr->y][curr->x] = 0;
			gotoxy(curr->x, curr->y);
			printf(" ");
			helpX = tempX;
			helpY = tempY;

			tempX = curr->x;
			tempY = curr->y;

			curr->x = helpX;
			curr->y = helpY;
		}

		map[curr->y][curr->x] = 2;
		gotoxy(curr->x, curr->y);
		printf("%c", 177);

		curr = curr->next;
	}
	return true;
}

void play(){
	char move;
	int dir = 4;
	bool walk = true;
	int speed;
	score = 0;
	while(walk){
		if(score>10)speed=150;
		else if(score>20)speed=100;
		else if(score<11) speed=200;
		else speed=50;
		
		if (kbhit()){
			switch(tolower(move = getch())){
			case 'w':
				if (dir != 3) dir = 1;
				if(dir==1)speed/=2;
				break;
			case 'a':
				if (dir != 4) dir = 2;
				if(dir==2)speed/=2;
				break;
			case 's':
				if (dir != 1) dir = 3;
				if(dir==3)speed/=2;
				break;
			case 'd':
				if (dir != 2) dir = 4;
				if(dir==4)speed/=2;
				break;
			}
		}

		switch(dir){
		case 1:
			walk = run(0, -1);
			break;
		case 2:
			walk = run(-1, 0);
			break;
		case 3:
			walk = run(0, 1);
			break;
		case 4:
			walk = run(1, 0);
			break;
		}

		gotoxy(1, sizeY + 1);
		printf("Scrore : %d", score);

		Sleep(speed);
	}
}
void popAll(){
	while(head){
		Body *curr;
		curr=head;
		head=head->next;
		free(curr);
	}
}

int main(){
	system("title ULER - Kevin Nicky Setiawan");
	int input=0;
	
	while(input!=2){
		system("cls");
		puts("1.play");
		puts("2.exit");
		scanf("%d",&input);ff;
		if(input==1){
			system("cls");
			createBody(4, 4);
			createMap();
			viewMap();
			play();
			gotoxy(1, sizeY + 2);
			printf("game over");
			char m;
			scanf("%c",&m);ff;
			
			popAll();
		}
	}

	return 0;
}