diff --git a/a2/snake.c b/a2/snake.c
new file mode 100644
index 0000000..b1843df
--- /dev/null
+++ b/a2/snake.c
@@ -0,0 +1,58 @@
+#include "snake.h"
+#include <stdlib.h>
+
+struct snake* add_snake(struct snake* snake,int x,int y){
+    struct snake* head = calloc(1,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* current = snake;
+    while (current->next->next != NULL) {
+        current = current->next;
+    }
+
+    free(current->next);
+    current->next = NULL;
+
+    return snake;
+}
+
+void free_snake(struct snake* sn) {
+    struct snake* current = sn;
+    struct snake* next;
+
+    while (current!= NULL) {
+        next = current->next;
+        free(current);
+        current = next;
+    }
+}
+
+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);
+    return END_CONTINUE;
+}