Added python3 shebangs

day18.py

@@ -0,0 +1,133 @@
+#!/usr/bin/env python3
+
+from functools import total_ordering
+from collections import defaultdict
+from itertools import combinations
+
+@total_ordering
+class MaxBound:
+    def __gt__(self, other):
+        return True
+
+    def __eq__(self, other):
+        return False
+
+    def __ge__(self, other):
+        return True
+
+    def __le__(self, other):
+        return False
+
+    def __repr__(self):
+        return "MaxBound"
+
+
+def move_func(maze, i):
+    w = maze.index('\n')+1
+    possible = i+1, i-1, i+w, i-w
+    return [j for j in possible if j < len(maze) and maze[j] not in ('\n', '#')]
+
+def build_branch(maze, i, w=0, visited=None, edges=None):
+    if visited == None:
+        visited = defaultdict(MaxBound)
+        edges = defaultdict(MaxBound)
+    if visited[i] <= w:
+        return
+    visited[i] = w
+    node = maze[i]
+    if node != '.' and w > 0:
+        edges[node] = min(edges[node], w)
+        return
+    for m in move_func(maze, i):
+        build_branch(maze, m, w+1, visited, edges)
+    return edges
+
+def build_graph(maze):
+    keys = [c for c in maze if c not in ('#', '.', '\n')]
+    graph = dict()
+    for key in keys:
+        graph[key] = build_branch(maze, maze.index(key))
+    return graph
+
+def print_graph(graph):
+    for node in graph:
+        print(node, end='')
+        for n, w in graph[node].items():
+            print("--{}--> {}".format(w, n))
+            print(' '*len(node), end='')
+        print()
+
+def unlock(graph, key):
+    new = dict()
+    if key not in graph:
+        return graph
+    for a in graph:
+        if a == key:
+            continue
+        new[a] = defaultdict(MaxBound)
+        for b, w in graph[a].items():
+            if b == key:
+                continue
+            new[a][b] = w
+    for a, b in combinations(graph[key].keys(), 2):
+        w = graph[key][a] + graph[key][b]
+        new[a][b] = new[b][a] = min(new[a][b], w)
+    return new
+
+def is_key(c):
+    return c == c.lower()
+
+def doorof(key):
+    return key.upper() if key.isalpha() else None
+
+def heu_sort(edges):
+    return sorted(edges.items(), key=lambda x: x[1])
+
+def search(graph, nodes, w=0, best=MaxBound(), d=0, mem=None, key=''):
+    if mem == None:
+        mem = defaultdict(MaxBound)
+
+    id = "".join(sorted(nodes)) + ''.join(sorted(n for n in graph if n not in nodes and is_key(n)))
+    if w >= best or w >= mem[id]:
+        return best
+
+    if len(mem) < 10**5:
+        mem[id] = w
+
+    graph = unlock(graph, doorof(key))
+
+    for i, node in enumerate(nodes):
+        bridged  = unlock(graph, node)
+
+        for n, w2 in heu_sort(graph[node]):
+            if not is_key(n):
+                continue
+            r = search(bridged, nodes[:i] + [n] + nodes[i+1:], w+w2, best, d+1, mem, n)
+            best = min(best, r)
+    if len(graph) == len(nodes) and w < best:
+        best = w
+    return best
+
+def init_maze(maze):
+    maze = list(maze)
+    for i in range(maze.count('@')):
+        maze[maze.index('@')] = str(i)
+    return ''.join(maze), map(str, range(i+1))
+
+def prepoc(puzzle_input):
+    return puzzle_input
+
+def partI(maze):
+    graph = build_graph(maze)
+    return search(graph, ['@'])
+
+def partII(maze):
+    maze = list(maze)
+    i = maze.index('@')
+    w = maze.index('\n')
+    maze[i-1:i+2] = '###'
+    maze[i-w-2:i-w+1] = maze[i+w:i+w+3] = '@#@'
+    maze, nodes = init_maze(maze)
+    graph = build_graph(maze)
+    return search(graph, list(nodes))
+

day19.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+
+from intcode import preproc
+
+def partI(exe):
+    mp = '\n'.join(''.join(str(next(exe(x, y))) for x in range(50))
+                                      for y in range(50))
+    return mp.count('1')
+
+def partII(exe):
+    def is_beam(x, y):
+        return next(exe(x, y)) == 1
+
+    xs = [(0, 0)]
+    y = 100
+    width = 0
+    while len(xs) < 100 or xs[0][1] - xs[-1][0] < 99:
+        x = xs[-1][0]
+        while not is_beam(x, y):
+            x += 1
+        start = x
+        x += width
+        while is_beam(x, y):
+            width += 1
+            x += 1
+        width -= 1
+        end = x-1
+        xs.append((start, end))
+        if len(xs) > 100:
+            xs = xs[-100:]
+        y += 1
+
+    X = start
+    Y = y - 100
+    return 10**4 * X + Y
+

day20.py

@@ -0,0 +1,266 @@
+#!/usr/bin/env python3
+
+from collections import defaultdict
+
+
+WALL = '#'
+PATH = '.'
+
+A = ("out", "AA")
+Z = ("out", "ZZ")
+
+
+class WeightedGraph(dict):
+    def edges_of(self, a):
+        return self[a]
+
+    def add_edge(self, a, b, w):
+        self[a].append((b, w))
+        self[b].append((a, w))
+
+    def add_node(self, a):
+        if a not in self:
+            self[a] = []
+
+    def rm_loops(self):
+        for a in self.keys():
+            for i, (b, w) in enumerate(self[a]):
+                if a == b:
+                    del self[a][i]
+
+    def min_path(self, a, b):
+        weights = dict() 
+        visited = set()
+
+        node, w = a, 0
+        while node != b:
+            for c, edge_w in self.edges_of(node):
+                if c in visited:
+                    continue
+                if c in weights and weights[c] <= w + edge_w:
+                    continue
+                weights[c] = w + edge_w
+            node, w = min(weights.items() , key=lambda nw: nw[1])
+            del weights[node]
+            visited.add(node)
+        return w 
+
+    def min_paths(self, a):
+        weights = dict()
+        def aux(a, w):
+            if a in weights.keys() and weights[a] <= w:
+                return
+
+            weights[a] = w
+
+            for b, ab_w in graph[node]:
+                best = aux(b, w + w2, best)
+
+        aux(a, 0, None)
+        return weights
+
+    def copy(self):
+        return WeightedGraph({a : [bw for bw in bws]for a, bws in self.items()})
+
+
+def neighbours(maze, vec):
+    x, y = vec
+    ns = [(x+1, y), (x-1, y), (x, y+1), (x, y-1)]
+    width = max(map(len, maze))
+    return filter(lambda vec: 0 <= vec[0] < len(maze) and 0 <= vec[1] < len(maze[x]), ns)
+
+def find_full_name(maze, vec):
+    x, y = vec
+    A = maze[x][y]
+    assert A.isalpha()
+    for a, b in neighbours(maze, (x, y)):
+        B = maze[a][b]
+        if B.isalpha():
+            return ''.join(sorted(A+B))
+    return None
+
+def find_node(maze, vec):
+    x, y = vec
+    width = max(map(len, maze))
+    name = find_full_name(maze, (x, y))
+    if x < 2 or len(maze) - 2 <= x or y < 2 or width - 2 <= y:
+        loc = "out"
+    else:
+        loc = "in"
+    node = (loc, name)
+    return node
+
+def other_node(packed):
+    loc, name = packed
+    if loc == "in":
+        return ("out", name)
+    return ("in", name)
+
+def make_graph(maze):
+    graph = dict()
+    def search(node, vec, w, visited):
+        x, y = vec
+        if (x, y) in visited:
+            return
+        visited.append((x, y))
+        c = maze[x][y]
+        if c.isalpha():
+            node2 = find_node(maze, (x, y))
+            if node != node2:
+                graph[node].append((node2, w-1))
+        elif c == PATH:
+            for n in neighbours(maze, (x, y)):
+                search(node, n, w+1, visited)
+
+    visited = []
+    for x, line in enumerate(maze):
+        for y, c in enumerate(line):
+            if not c.isalpha():
+                continue
+            node = find_node(maze, (x, y))
+            if node in visited:
+                continue
+            paths = [(x,y) for (x,y) in neighbours(maze, (x,y)) if maze[x][y] == PATH]
+            if paths == []:
+                continue
+            visited.append(node)
+            start = paths[0]
+            graph[node] = []
+            search(node, start, 0, [])
+    graph = WeightedGraph(graph)
+    graph.rm_loops()
+    return graph
+
+def preproc(puzzle_input):
+    maze = puzzle_input.split('\n')
+    return make_graph(maze)
+
+def partI(graph):
+    graph = graph.copy()
+    for node in graph.keys():
+        if node[1] in ["AA", "ZZ"]:
+            continue
+        graph.add_edge(node, other_node(node), 1)
+    return graph.min_path(A, Z)
+
+class RecGraph(WeightedGraph):
+    def edges_of(self, packed):
+        lvl, a = packed
+        edges = [((lvl, b), w) for b, w in self[a]]
+
+        loc, _ = a
+
+        lvl2 = lvl + (1 if loc == "in" else -1)
+        b = other_node(a)
+
+        if b not in self or lvl2 < 0:
+            return edges
+        b_edge = (lvl2, b), 1
+        if lvl2 < lvl:
+            edges = [b_edge] + edges
+        else:
+            edges.append(b_edge)
+        return edges
+
+
+def partII(graph):
+    graph = RecGraph(graph)
+    return graph.min_path((0, A), (0, Z))
+
+test ="""         A           
+         A           
+  #######.#########  
+  #######.........#  
+  #######.#######.#  
+  #######.#######.#  
+  #######.#######.#  
+  #####  B    ###.#  
+BC...##  C    ###.#  
+  ##.##       ###.#  
+  ##...DE  F  ###.#  
+  #####    G  ###.#  
+  #########.#####.#  
+DE..#######...###.#  
+  #.#########.###.#  
+FG..#########.....#  
+  ###########.#####  
+             Z       
+             Z       """
+
+
+test2 = """                   A               
+                   A               
+  #################.#############  
+  #.#...#...................#.#.#  
+  #.#.#.###.###.###.#########.#.#  
+  #.#.#.......#...#.....#.#.#...#  
+  #.#########.###.#####.#.#.###.#  
+  #.............#.#.....#.......#  
+  ###.###########.###.#####.#.#.#  
+  #.....#        A   C    #.#.#.#  
+  #######        S   P    #####.#  
+  #.#...#                 #......VT
+  #.#.#.#                 #.#####  
+  #...#.#               YN....#.#  
+  #.###.#                 #####.#  
+DI....#.#                 #.....#  
+  #####.#                 #.###.#  
+ZZ......#               QG....#..AS
+  ###.###                 #######  
+JO..#.#.#                 #.....#  
+  #.#.#.#                 ###.#.#  
+  #...#..DI             BU....#..LF
+  #####.#                 #.#####  
+YN......#               VT..#....QG
+  #.###.#                 #.###.#  
+  #.#...#                 #.....#  
+  ###.###    J L     J    #.#.###  
+  #.....#    O F     P    #.#...#  
+  #.###.#####.#.#####.#####.###.#  
+  #...#.#.#...#.....#.....#.#...#  
+  #.#####.###.###.#.#.#########.#  
+  #...#.#.....#...#.#.#.#.....#.#  
+  #.###.#####.###.###.#.#.#######  
+  #.#.........#...#.............#  
+  #########.###.###.#############  
+           B   J   C               
+           U   P   P              """ 
+
+test3 = """             Z L X W       C                 
+             Z P Q B       K                 
+  ###########.#.#.#.#######.###############  
+  #...#.......#.#.......#.#.......#.#.#...#  
+  ###.#.#.#.#.#.#.#.###.#.#.#######.#.#.###  
+  #.#...#.#.#...#.#.#...#...#...#.#.......#  
+  #.###.#######.###.###.#.###.###.#.#######  
+  #...#.......#.#...#...#.............#...#  
+  #.#########.#######.#.#######.#######.###  
+  #...#.#    F       R I       Z    #.#.#.#  
+  #.###.#    D       E C       H    #.#.#.#  
+  #.#...#                           #...#.#  
+  #.###.#                           #.###.#  
+  #.#....OA                       WB..#.#..ZH
+  #.###.#                           #.#.#.#  
+CJ......#                           #.....#  
+  #######                           #######  
+  #.#....CK                         #......IC
+  #.###.#                           #.###.#  
+  #.....#                           #...#.#  
+  ###.###                           #.#.#.#  
+XF....#.#                         RF..#.#.#  
+  #####.#                           #######  
+  #......CJ                       NM..#...#  
+  ###.#.#                           #.###.#  
+RE....#.#                           #......RF
+  ###.###        X   X       L      #.#.#.#  
+  #.....#        F   Q       P      #.#.#.#  
+  ###.###########.###.#######.#########.###  
+  #.....#...#.....#.......#...#.....#.#...#  
+  #####.#.###.#######.#######.###.###.#.#.#  
+  #.......#.......#.#.#.#.#...#...#...#.#.#  
+  #####.###.#####.#.#.#.#.###.###.#.###.###  
+  #.......#.....#.#...#...............#...#  
+  #############.#.#.###.###################  
+               A O F   N                     
+               A A D   M                     """
+

day21.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+
+from intcode import preproc
+from lib import last
+
+logic1 = """\
+NOT A J
+NOT B T
+OR T J
+NOT C T
+OR T J
+AND D J
+"""
+logic2 = logic1 + """\
+NOT I T
+NOT T T
+OR F T
+AND E T
+OR H T
+AND T J
+"""
+
+def partI(exe):
+    log = logic1 + 'WALK\n'
+    return last(exe(input_iter = map(ord, log)))  
+
+def partII(exe):
+    log = logic2 + 'RUN\n'
+    return last(exe(input_iter = map(ord, log)))  
+
+

day22.py

@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+
+from functools import reduce
+
+deal  = lambda: (-1, -1)
+dealN = lambda n: (n, 0)
+cutN  = lambda n: (1, -n)
+id    = (1, 0)
+
+instructions = {"deal into new stack" : deal,
+                "deal with increment" : dealN,
+                "cut" :                 cutN
+               }
+
+def egcd(a, b):
+    if a == 0:
+        return (b, 0, 1)
+    else:
+        g, y, x = egcd(b % a, a)
+        return (g, x - (b // a) * y, y)
+
+def modinv(a, m):
+    g, x, y = egcd(a, m)
+    if g != 1:
+        raise Exception('modular inverse does not exist')
+    else:
+        return x % m
+
+def comp(ab, cd, mod):
+    a, b = ab
+    c, d = cd
+    return ((a*c) % mod, (a*d + b) % mod)
+
+def apply(ab, x, mod):
+    a, b = ab
+    return (a*x + b) % mod
+
+def inverse(ab, mod):
+    a, b = ab
+    x = modinv(a, mod)
+    return (x, (-b * x) % mod)
+
+def powcomp(ab, pw, mod):
+    a, b = ab
+    return (pow(a, pw, mod), ((pow(a, pw, mod) - 1) * modinv(a-1, mod) * b) % mod)
+
+def parse(line):
+    for inst in instructions.keys():
+        if line[:len(inst)] == inst:
+            return instructions[inst](*map(int, line[len(inst):].split()))
+    return NotImplemented
+
+def compile(program, deck):
+    return reduce(lambda f1, f2: comp(f2, f1, deck), program, id)
+
+
+def preproc(puzzle_input):
+    return list(map(parse, puzzle_input.split('\n')))
+
+def partI(program):
+    deck = 10007
+    shuffle = compile(program, deck)
+    return apply(shuffle, 2019, deck)
+
+def partII(program):
+    deck = 119315717514047
+    pw   = 101741582076661
+    shuffle = compile(program, deck)
+    invshuffle = inverse(shuffle, deck)
+
+    repeated = powcomp(invshuffle, pw, deck)
+    return apply(repeated, 2020, deck)

day24.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python3
+
+BUG = '#'
+EMPTY = '.'
+LEVEL = '.'*12 + '?' + '.'*12
+
+edges = {7  : range(0, 5),
+         11 : range(0, 21, 5),
+         13 : range(4, 25, 5),
+         17 : range(20, 25)}
+
+
+def neighbours(lvl, i):
+    r = []
+    if i > 4:
+        r.append(i-5)
+    if i < 20:
+        r.append(i+5)
+    if (i % 5) < 4:
+        r.append(i+1)
+    if (i % 5) > 0:
+        r.append(i-1)
+    return list(zip(4*[lvl], r))
+
+def rec_neigh(lvl, i):
+    ns = neighbours(lvl, i)
+    for inner, outer in edges.items():
+        if i == inner:
+            ns += [(lvl+1, j) for j in outer]
+        elif i in outer:
+            ns += [(lvl-1, inner)]
+    return ns
+
+def fate(val, ns):
+    if val == BUG and ns.count(BUG) != 1:
+        return EMPTY
+    elif val == EMPTY and ns.count(BUG) in (1, 2):
+        return BUG
+    return val
+
+def trim(stack):
+    while BUG not in stack[-1]:
+        stack.pop()
+    while BUG not in stack[0]:
+        stack.pop(0)
+
+def next(bug_stack, nfunc=rec_neigh):
+    bug_stack = 2*[LEVEL] + bug_stack + 2*[LEVEL]
+    new = []
+    for lvl in range(1, len(bug_stack)-1):
+        new.append('')
+        for i, val in enumerate(bug_stack[lvl]):
+            ns = nfunc(lvl, i)
+            nvals = [bug_stack[l][j] for l, j in ns]
+            new[-1] += fate(val, nvals)
+    trim(new)
+    return new
+
+def bugs_sim(bug_stack, i):
+    for i in range(i):
+        bug_stack = next(bug_stack)
+    return bug_stack
+
+def biodiversity(bugs):
+    return sum(2**pw for pw, c in enumerate(bugs) if c == BUG)
+
+def preproc(puzzle_input):
+    return puzzle_input.replace('\n', '')
+
+def partI(bugs):
+    layouts = set()
+    b = bugs
+    while b not in layouts:
+        layouts.add(b)
+        b = next([b], neighbours)[0]
+
+    return biodiversity(b)
+
+def partII(bugs):
+    bugs = bugs[:12] + '?' + bugs[13:]
+    stack = [bugs]
+    return ''.join(bugs_sim(stack, 200)).count(BUG)