1 files changed, 64 insertions, 0 deletions
diff --git a/advent-of-code/2022/05/2.c b/advent-of-code/2022/05/2.c
new file mode 100644
index 0000000..8a3215d
--- /dev/null
+++ b/advent-of-code/2022/05/2.c
@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+struct listnode {
+    struct listnode *next;
+    char val;
+};
+typedef struct {
+    struct listnode *head;
+} Stack;
+
+void stack_push(Stack *s, char val) {
+    struct listnode *n = malloc(sizeof(struct listnode));
+    n->next = s->head;
+    n->val = val;
+    s->head = n;
+}
+
+char* stack_top(Stack *s) {
+    if (s->head == NULL) return NULL;
+    return &(s->head->val);
+}
+
+void stack_pop(Stack *s) {
+    if (s->head == NULL) return;
+    struct listnode *next = s->head->next;
+    free(s->head);
+    s->head = next;
+}
+
+char buf[4096];
+
+int main() {
+    Stack s[9];
+    FILE *fp = fopen("input", "r");
+    fread(buf, 1, 36 * 8, fp);
+    for (int i = 0; i < 9; i++) {
+        for (int j = 0; j < 8; j++) {
+            char c = buf[(7 - j) * 36 + i * 4 + 1];
+            if (c != ' ') {
+                stack_push(&s[i], c);
+            }
+        }
+    }
+    fgets(buf, 4096, fp);
+    fgets(buf, 4096, fp);
+    int amount, from, to;
+    while (fscanf(fp, "move %d from %d to %d\n", &amount, &from, &to) > 0) {
+        for (int i = 0; i < amount; i++) {
+            char c = *stack_top(&s[from - 1]);
+            stack_pop(&s[from - 1]);
+            buf[i] = c;
+        }
+        for (int i = 0; i < amount; i++) {
+            int n = amount - i - 1;
+            stack_push(&s[to-1], buf[n]);
+        }
+    }
+    for (int i = 0; i < 9; i++) {
+        printf("%c", *stack_top(&s[i]));
+    }
+    printf("\n");
+    return 0;
+}