2020 day 25 (C): just copied my (lazy/brute-force) bash solution

2020/day19/ex1-c.c

@@ -1,4 +1,4 @@
-/* ex1-c: Advent2020 game, day 18/tasks 1 & 2
+/* ex1-c: Advent2020 game, day 19/tasks 1 & 2
  */
 
 #include <stdio.h>
@@ -6,168 +6,11 @@
 #include <string.h>
 #include <assert.h>
 
-#define T_LPAR   (-'(')
-#define T_RPAR   (-')')
-
-#define T_PLUS   (-'+')
-#define T_MULT   (-'*')
-
-#define T_ERR    (-'E')
-#define T_OK     (-'O')
-#define T_END    (-'$')
-
-#define LEN_MAX  1024
-
-#define NPUSH(n) (push(&nstack, (n)))
-#define OPUSH(o) (push(&ostack, (o)))
-
-#define NPOP()   (pop(&nstack))
-#define OPOP()   (pop(&ostack))
-
-#define NTOP()   (top(&nstack))
-#define OTOP()   (top(&ostack))
-
-#define OEMPTY() (empty(&ostack))
-
-#define DIGIT(c) (((c) >= '0') && ((c) <= '9'))
-
-static struct stack {
-    int last;
-    long elt[LEN_MAX];
-} nstack, ostack;
-
-static char *saveptr=NULL;
-
-static int prio_1(long op)
-{
-    return op==T_PLUS || op==T_MULT? 1: 0;
-}
-static int prio_2(long op)
-{
-    return op==T_PLUS? 2: op==T_MULT? 1: 0;
-}
-static int (*prio)()=&prio_1;
-
-static long push(struct stack *s, long val)
-{
-    s->elt[s->last++]=val;
-    return val;
-}
-static long pop(struct stack *s)
-{
-    return s->elt[--s->last];
-}
-static long top(struct stack *s)
-{
-    return s->elt[s->last-1];
-}
-static long empty(struct stack *s)
-{
-    return s->last==0;
-}
-
-static void print() {
-    int i;
-    printf("NSTACK: ");
-    for (i=0; i<nstack.last; ++i) {
-        printf("%ld ", nstack.elt[i]);
-    }
-    printf("\nOSTACK: ");
-    for (i=0; i<ostack.last; ++i) {
-        printf("%c ", (char) -ostack.elt[i]);
-    }
-    printf("\n");
-}
-static long get_tok()
-{
-    char *p, c;
-    long val=0;
-
-    p=saveptr;
-    while (!val) {
-        c=*p;
-        switch (c) {
-            case ' ':
-                break;
-            case '(':
-                   case ')':
-            case '*':
-            case '+':
-                val=-c;
-                break;
-            case '\n':
-            case '\0':
-                val=T_END;
-                break;
-            default:
-                if (! DIGIT(c)) {
-                    val=T_ERR;
-                    break;
-                }
-                while (DIGIT(c)) {
-                    val=(val*10 + c - '0');
-                    p++;
-                    c=*p;
-                }
-                p--;
-                break;
-        }
-        p++;
-    }
-    saveptr=p;
-    return val;
-}
-
-static long eval_top()
-{
-    long val2 = NPOP();
-    long val1 = NPOP();
-    char op = OPOP();
-    NPUSH(op==T_PLUS? val1+val2: val1*val2);
-    return NTOP();
-}
-
-static long eval_expr()
-{
-    long res=T_LPAR;
-
-    res=get_tok();
-    while (res!=T_ERR && res!=T_END) {
-        switch (res) {
-            case T_LPAR:
-                OPUSH(res);
-                break;
-            case T_RPAR:
-                while(!OEMPTY() && OTOP() != T_LPAR)
-                    eval_top();
-                if(!OEMPTY())                     // remove '('
-                    OPOP();
-                break;
-            case T_PLUS:
-            case T_MULT:
-
-                while (!OEMPTY() && (*prio)(OTOP()) >= (*prio)(res))
-                    eval_top();
-                OPUSH(res);
-                break;
-
-            default:
-                NPUSH(res);
-                break;
-        }
-        res=get_tok();
-        //print();
-    }
-    while(!OEMPTY())
-        eval_top();
-
-    // return NSTACK's top
-    //printf("Returning %ld\n", NTOP());
-    return NPOP();
-//end:
-//    return left;
-}
+struct rule {
+    struct rule *left;
+    struct rule *right;
 
+};
 int main(ac, av)
     int ac;
     char **av;