1 files changed, 122 insertions, 0 deletions
diff --git a/2022/day05/main.c b/2022/day05/main.c
new file mode 100644
index 0000000..f6af2ea
--- /dev/null
+++ b/2022/day05/main.c
@@ -0,0 +1,122 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+
+struct StackItem_;
+
+typedef struct StackItem_ {
+    char value;
+    struct StackItem_ *next, *prev;
+} StackItem;
+
+typedef struct Stack_ {
+    StackItem *top, *bottom;
+} Stack;
+
+void push_top(Stack *stack, StackItem *item) {
+    if (stack->top)
+    {
+        StackItem* old = stack->top;
+        old->next = item;
+        item->prev = old;
+    }
+    if (!stack->top) stack->bottom = item;
+    stack->top = item;
+}
+
+void push_back(Stack *stack, StackItem *item) {
+    if (stack->bottom)
+    {
+        StackItem* old = stack->bottom;
+        old->prev = item;
+        item->next = old;
+    }
+    if (!stack->bottom) stack->top = item;
+    stack->bottom = item;
+}
+
+StackItem* pop_top(Stack *stack) {
+    StackItem* old = stack->top;
+    stack->top = old->prev;
+    if (old->prev != 0)
+    {
+        stack->top->next = 0;
+    }
+    old->next = old->prev = 0;
+
+    return old;
+}
+
+StackItem* pop_back(Stack *stack) {
+    StackItem* old = stack->bottom;
+    stack->bottom = old->next;
+    stack->bottom->prev = 0;
+    old->next = old->prev = 0;
+
+    return old;
+}
+
+void printCargo(Stack *cargo, size_t len) 
+{
+    for (int i = 0; i < len; i++)
+    {
+        for ( StackItem *e = cargo[i].bottom; e != 0; e = e->next )
+        {
+            printf("%c", e->value);
+        }
+        printf("\n");
+    }
+}
+
+int main()
+{
+    char *line = 0;
+    size_t len;
+    Stack *cargo;
+    size_t cargos;
+    ssize_t nread;
+
+    int amount, from, to;
+
+    while ((nread = getline(&line, &len, stdin)) != 0)
+    {
+        if ( line[1] == '1' ) continue;
+        if ( line[0] == '\n' ) break;
+        if ( !cargo ) {
+            cargos = (nread+1)/4;
+            cargo = (Stack*)malloc( sizeof(Stack) * cargos );
+        }
+
+        for (int i = 0; i < cargos; i++ ) {
+            char load = line[i*4+1];
+            if ( load != ' ' ) {
+                StackItem *box = malloc(sizeof(StackItem));
+                box->value = line[i*4+1];
+                box->next = box->prev = 0;
+                push_back(&cargo[i], box);
+            } 
+        }
+    }
+
+    printCargo(cargo, cargos);
+    printf("---------------\n");
+
+    while (scanf("move %d from %d to %d\n", &amount, &from, &to) != EOF)
+    {
+        printf( "%d %d %d\n", amount, from, to );
+        for (int i = 0; i < amount; i++)
+        {
+            StackItem *item = pop_top(&cargo[from-1]);
+            push_top(&cargo[to-1], item);
+            
+            printCargo(cargo, cargos);
+            printf("---------------\n");
+        }
+    }
+
+    for ( int i = 0; i < cargos; i++ )
+    {
+        printf( "%c", cargo[i].top->value );
+    }
+    printf("\n");
+}