2018 day 20 wip

2018/d20.py

@@ -15,7 +15,60 @@ DIRS = {
 
 
 def part_1(data):
-    data = data[1:]
+    g = defaultdict(set)
+
+    stack: list[tuple[tuple, int, list]] = [((0, 0), 0, [])]
+    while len(stack) > 0:
+        pos, i, i_outs = stack.pop()
+        assert i is not None
+        while i < len(data):
+            c = data[i]
+            if c in DIRS.keys():
+                npos = add2(pos, DIRS[c])
+                g[pos].add(npos)
+                g[npos].add(pos)
+                pos = npos
+                i += 1
+            elif c == "(":
+                to_continue = [i + 1]
+                open_count = 0
+                j_out = None
+                for j in range(i + 1, len(data)):
+                    c = data[j]
+                    if c == "|" and open_count == 0:
+                        to_continue.append(j + 1)
+                    elif c == "(":
+                        open_count += 1
+                    elif c == ")" and open_count != 0:
+                        open_count -= 1
+                    elif c == ")" and open_count == 0:
+                        j_out = j
+                        break
+                assert j_out is not None
+
+                for new_i in to_continue:
+                    new_i_outs = list(i_outs)
+                    new_i_outs.append(j_out)
+                    stack.append((pos, new_i, new_i_outs))
+                break
+            elif c == "$":
+                break
+            elif c == ")" and len(i_outs) == 0:
+                assert False, "Encountered | without i_out"
+            elif c == ")":
+                i_new = i_outs.pop()
+                assert i == i_new
+                i += 1
+            elif c == "^":
+                i += 1
+            elif c == "|" and len(i_outs) == 0:
+                assert False, "Encountered | without i_out"
+            elif c == "|":
+                i = i_outs.pop()
+                i += 1
+            else:
+                assert False
+
 
     # def parse(i):
     #     max_len = 0
@@ -45,39 +98,39 @@ def part_1(data):
     #
     # print(parse(0)[0])
 
-    g = defaultdict(set)
-    def parse(xs, i):
-        xs_orig = xs.copy()
-        xs_done = []
-
-        while i < len(data):
-            c = data[i]
-            if c in DIRS.keys():
-                for xi in range(len(xs)):
-                    pos = xs[xi]
-                    npos = add2(pos, DIRS[c])
-                    g[pos].add(npos)
-                    g[npos].add(pos)
-                    xs[xi] = npos
-                i += 1
-            elif c == "(":
-                xs, i = parse(xs, i + 1)
-            elif c == "|":
-                xs_done += xs
-                xs = xs_orig
-                i += 1
-            elif c == ")":
-                xs_done += xs
-                return xs_done, i + 1
-            elif c == "$":
-                xs_done += xs
-                i += 1
-            else:
-                assert False
-        return xs_done, i
-
-    parse([(0, 0)], 0)
-
+    # g = defaultdict(set)
+    # def parse(xs, i):
+    #     xs_orig = xs.copy()
+    #     xs_done = []
+    #
+    #     while i < len(data):
+    #         c = data[i]
+    #         if c in DIRS.keys():
+    #             for xi in range(len(xs)):
+    #                 pos = xs[xi]
+    #                 npos = add2(pos, DIRS[c])
+    #                 g[pos].add(npos)
+    #                 g[npos].add(pos)
+    #                 xs[xi] = npos
+    #             i += 1
+    #         elif c == "(":
+    #             xs, i = parse(xs, i + 1)
+    #         elif c == "|":
+    #             xs_done += xs
+    #             xs = xs_orig
+    #             i += 1
+    #         elif c == ")":
+    #             xs_done += xs
+    #             return xs_done, i + 1
+    #         elif c == "$":
+    #             xs_done += xs
+    #             i += 1
+    #         else:
+    #             assert False
+    #     return xs_done, i
+    #
+    # parse([(0, 0)], 0)
+ 
     seen = set()
     dists = {}
     xs = [(0, 0)]

2020/d8.py

@@ -0,0 +1,71 @@
+from lib import get_data, str_to_ints
+
+
+def part_1(data):
+    insts = data.splitlines()
+    acc = 0
+    i = 0
+    seen = set()
+
+    while i < len(insts) and i not in seen:
+        inst = insts[i]
+        seen.add(i)
+        if inst.startswith("acc"):
+            (v,) = str_to_ints(inst)
+            acc += v
+            i += 1
+        elif inst.startswith("jmp"):
+            (v,) = str_to_ints(inst)
+            i += v
+        elif inst.startswith("nop"):
+            i += 1
+        else:
+            assert False
+
+    print(acc)
+
+    for j in range(len(insts)):
+
+        if "jmp" in insts[j]:
+            insts[j] = insts[j].replace("jmp", "nop")
+        elif "nop" in insts[j]:
+            insts[j] = insts[j].replace("nop", "jmp")
+        else:
+            continue
+
+        i = 0
+        acc = 0
+        seen = set()
+        while i < len(insts) and i not in seen:
+            inst = insts[i]
+            seen.add(i)
+            if inst.startswith("acc"):
+                (v,) = str_to_ints(inst)
+                acc += v
+                i += 1
+            elif inst.startswith("jmp"):
+                (v,) = str_to_ints(inst)
+                i += v
+            elif inst.startswith("nop"):
+                i += 1
+            else:
+                assert False
+
+        if not i in seen:
+            print(acc)
+
+        if "jmp" in insts[j]:
+            insts[j] = insts[j].replace("jmp", "nop")
+        elif "nop" in insts[j]:
+            insts[j] = insts[j].replace("nop", "jmp")
+        else:
+            continue
+
+
+def main():
+    data = get_data(__file__)
+    part_1(data)
+
+
+if __name__ == "__main__":
+    main()