Solve 2020/23

2020/22/example

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+Player 1:
+9
+2
+6
+3
+1
+
+Player 2:
+5
+8
+4
+7
+10

2020/22/example2

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+Player 1:
+43
+19
+
+Player 2:
+2
+29
+14
+

2020/22/input

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+Player 1:
+31
+24
+5
+33
+7
+12
+30
+22
+48
+14
+16
+26
+18
+45
+4
+42
+25
+20
+46
+21
+40
+38
+34
+17
+50
+
+Player 2:
+1
+3
+41
+8
+37
+35
+28
+39
+43
+29
+10
+27
+11
+36
+49
+32
+2
+23
+19
+9
+13
+15
+47
+6
+44

2020/22/solution1.py

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+
+from collections import deque
+
+
+p1 = deque()
+p2 = deque()
+
+
+with open('input', 'r') as f:
+    f.readline()  # player 1
+    while (line := f.readline()) and line != '\n':
+        p1.append(int(line))
+    f.readline()  # player 2
+    while (line := f.readline()) and line != '\n':
+        p2.append(int(line))
+
+
+print(p1)
+print(p2)
+
+while len(p1) and len(p2):
+    a = p1.popleft()
+    b = p2.popleft()
+    winner = p1 if a > b else p2
+    winner.append(max(a, b))
+    winner.append(min(a, b))
+
+print(p1)
+print(p2)
+
+winner = p1 if len(p1) else p2
+i = 1
+score = 0
+while len(winner):
+    score += winner.pop() * i
+    i += 1
+
+print(score)

2020/22/solution2.py

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+
+from collections import deque
+
+
+p1 = deque()
+p2 = deque()
+
+
+with open('input', 'r') as f:
+    f.readline()  # player 1
+    while (line := f.readline()) and line != '\n':
+        p1.append(int(line))
+    f.readline()  # player 2
+    while (line := f.readline()) and line != '\n':
+        p2.append(int(line))
+
+print('p1:', p1)
+print('p2:', p2)
+
+
+def game(p1, p2):
+    rounds = set()
+    while len(p1) and len(p2):
+        # prevent infinite games
+        round_hash = str(p1) + str(p2)
+        if round_hash in rounds:
+            return 1
+        rounds.add(round_hash)
+
+        a = p1.popleft()
+        b = p2.popleft()
+
+        # check if each player has enough cards for recursion
+        if len(p1) >= a and len(p2) >= b:
+            new_p1 = p1.copy()
+            new_p2 = p2.copy()
+            while len(new_p1) > a:
+                new_p1.pop()
+            while len(new_p2) > b:
+                new_p2.pop()
+            winner = game(new_p1, new_p2)
+        else:
+            # normal round
+            winner = 1 if a > b else 2
+
+        # append cards to winner
+        winning_player = p1 if winner == 1 else p2
+        winning_player.append(a if winner == 1 else b)
+        winning_player.append(b if winner == 1 else a)
+    return 1 if len(p1) else 2
+
+
+game(p1, p2)
+
+print('After game:')
+print('p1:', p1)
+print('p2:', p2)
+winner = p1 if len(p1) else p2
+i = 1
+score = 0
+while len(winner):
+    score += winner.pop() * i
+    i += 1
+
+print('Score:')
+print(score)

2020/23/solution1.py

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+"""Solution to 2020/23"""
+
+from collections import deque
+
+EXAMPLE = '389125467'
+INPUT = '952316487'
+
+# INPUT = EXAMPLE
+
+MOVES = 100
+
+
+def main():
+    all_cups = deque(sorted(INPUT))
+    cups = deque(INPUT)
+
+    for move in range(MOVES):
+        print(f'-- MOVE {move + 1} --')
+        while all_cups[0] != cups[0]:
+            all_cups.rotate()
+        print(f'cups: {list(cups)}')
+        cur = cups[0]
+
+        cups.rotate(-1)
+        lift = [cups.popleft(), cups.popleft(), cups.popleft()]
+        next_cup = cups[0]
+        print('pick up:', lift)
+
+        all_cups.rotate()
+        while all_cups[0] in lift:
+            all_cups.rotate()
+        destination = all_cups[0]
+        print('destination:', destination)
+
+        while cups[-1] != destination:
+            cups.rotate()
+        cups.extend(lift)
+
+        while cups[0] != next_cup:
+            cups.rotate()
+
+    print('-- Final:--')
+    print(cups)
+    print()
+
+    while cups[0] != '1':
+        cups.rotate()
+    cups.popleft()
+    print(''.join(list(cups)))
+
+
+main()

2020/23/solution2.py

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+"""Solution to 2020/23"""
+
+from collections import deque
+
+EXAMPLE = '389125467'
+INPUT = '952316487'
+
+# INPUT = EXAMPLE
+
+MOVES = 10_000_000
+
+INPUT = list(map(int, INPUT))
+INPUT = INPUT + list(range(max(INPUT) + 1, 1_000_000 + 1))
+
+
+def main():
+    cups = CrabCups(INPUT)
+    print(cups)
+
+    for move in range(MOVES):
+        if move % 1_000_000 == 0:
+            print(f'-- MOVE {move} --')
+        cups.move()
+
+    print()
+    print('finished')
+    print(cups._nodes[1].next.value * cups._nodes[1].next.next.value)
+
+    exit()
+
+
+class CrabCups:
+    def __init__(self, cups):
+        nodes = dict()
+        i = 0
+        prev = None
+        while i < len(cups):
+            node = Node(cups[i])
+            if prev:
+                node.prev = prev
+                prev.next = node
+            prev = node
+            nodes[cups[i]] = node
+            i += 1
+        nodes[cups[0]].prev = nodes[cups[-1]]
+        nodes[cups[-1]].next = nodes[cups[0]]
+        self._nodes = nodes
+        self.cur = nodes[cups[0]]
+        self.cup_count = len(cups)
+        self.last_cur = None
+        self.last_pick_up = None
+        self.last_destination = None
+
+    def move(self):
+        pick_up = set()
+        link = self.cur
+        self.last_cur = self.cur
+        self.last_pick_up = link.next
+        for _ in range(3):
+            link = link.next
+            pick_up.add(link.value)
+
+        # wire cur with cup after pickups
+        link.next.prev = self.cur
+        self.cur.next = link.next
+
+        # find dest
+        dest = self.cur.value - 1
+        dest = dest if dest != 0 else self.cup_count
+        while dest in pick_up:
+            dest -= 1
+            dest = dest if dest != 0 else self.cup_count
+        dest = self._nodes[dest]
+        self.last_dest = dest
+
+        dest.next.prev = link
+        link.next = dest.next
+
+        link = link.prev.prev
+        dest.next = link
+        link.prev = dest
+
+        self.cur = self.cur.next
+
+    def as_list(self, start):
+        cups = [start.value]
+        cur = start.next
+        while not cur is start:
+            cups.append(cur.value)
+            cur = cur.next
+        return cups
+
+
+class Node:
+    next = None
+    prev = None
+
+    def __init__(self, val):
+        self.value = val
+
+
+main()