pvjc26/du4/snake.c

66 lines
1.6 KiB
C

#include "snake.h"
#include <stdlib.h>
struct snake* add_snake(struct snake* snake, int x, int y){
struct snake* head = malloc(sizeof(struct snake));
head->x = x;
head->y = y;
head->next = snake;
return head;
}
struct snake* remove_snake(struct snake* snake){
if(snake == NULL) return NULL;
if(snake->next == NULL){
free(snake);
return NULL;
}
struct snake* cur = snake;
while(cur->next->next != NULL)
cur = cur->next;
free(cur->next);
cur->next = NULL;
return snake;
}
void free_snake(struct snake* sn){
while(sn != NULL){
struct snake* tmp = sn->next;
free(sn);
sn = tmp;
}
}
int is_snake(struct snake* snake, int x, int y){
while(snake != NULL){
if(snake->x == x && snake->y == y) return 1;
snake = snake->next;
}
return 0;
}
int step_state(struct state* st){
int nx = st->snake->x + st->sx;
int ny = st->snake->y + st->sy;
if(nx < 0 || nx >= st->width || ny < 0 || ny >= st->height)
return END_WALL;
if(is_snake(st->snake, nx, ny))
return END_SNAKE;
for(int i = 0; i < FOOD_COUNT; i++){
if(st->foodx[i] == nx && st->foody[i] == ny){
st->snake = add_snake(st->snake, nx, ny);
st->foodx[i] = -1;
st->foody[i] = -1;
for(int j = 0; j < FOOD_COUNT; j++)
if(st->foodx[j] >= 0) return END_CONTINUE;
return END_FOOD;
}
}
st->snake = add_snake(st->snake, nx, ny);
st->snake = remove_snake(st->snake);
return END_CONTINUE;
}