Solve 2015 days 20-22.

2015/d20.py

@@ -0,0 +1,28 @@
+from itertools import combinations
+import lib
+
+data = int(open(0).read().strip())
+part_1 = False
+
+def calc(n):
+    fs = lib.prime_factors(n)
+    vs = set([1, n])
+    for i in range(1, len(fs) + 1):
+        for c in combinations(fs, i):
+            p = 1
+            for e in c:
+                p *= e
+            vs.add(p)
+    r = 0
+    for e in vs:
+        if part_1:
+            r += e * 10
+        elif n <= e * 50:
+            r += e * 11
+    return r
+
+for i in range(3, 10000000):
+    c = calc(i)
+    if c >= data:
+        print(i)
+        break

2015/d21.py

@@ -0,0 +1,89 @@
+from itertools import combinations
+
+data = open(0).read().strip()
+
+# hit points, damage, armor
+enemy = [100, 8, 2]
+
+weapons = [
+    [8, 4, 0],
+    [10, 5, 0],
+    [25, 6, 0],
+    [40, 7, 0],
+    [74, 8, 0],
+]
+
+# Armor:      Cost  Damage  Armor
+armor = [
+    [13, 0, 1],
+    [31, 0, 2],
+    [53, 0, 3],
+    [75, 0, 4],
+    [102, 0, 5],
+]
+
+rings = [
+    [25, 1, 0],
+    [50, 2, 0],
+    [100, 3, 0],
+    [20, 0, 1],
+    [40, 0, 2],
+    [80, 0, 3],
+]
+
+
+def player_configs():
+    for wc, wd, wa in weapons:
+        for ac, ad, aa in armor:
+            for i in range(1, 3):
+                for rgs in combinations(rings, i):
+                    c = wc + ac
+                    d = wd + ad
+                    a = wa + aa
+                    for rc, rd, ra in rgs:
+                        c += rc
+                        d += rd
+                        a += ra
+                    yield (c, d, a)
+            c = wc + ac
+            d = wd + ad
+            a = wa + aa
+            yield (c, d, a)
+        for i in range(1, 3):
+            for rgs in combinations(rings, i):
+                c = wc
+                d = wd
+                a = wa
+                for rc, rd, ra in rgs:
+                    c += rc
+                    d += rd
+                    a += ra
+                yield (c, d, a)
+
+
+def simulate(player, enemey):
+    ppoints, pdamage, parmor = player
+    epoints, edamage, earmor = enemey
+
+    while ppoints > 0 and epoints > 0:
+        epoints -= max(pdamage - earmor, 1)
+        ppoints -= max(edamage - parmor, 1)
+
+    if epoints <= 0:
+        return True
+    return False
+
+
+part_1 = False
+if part_1:
+    min_win = float("inf")
+    for c, d, a in player_configs():
+        if simulate([100, d, a], list(enemy)):
+            min_win = min(c, min_win)
+    print(min_win)
+else:
+    max_loss = 0
+    for c, d, a in player_configs():
+        if not simulate([100, d, a], list(enemy)):
+            max_loss = max(c, max_loss)
+    print(max_loss)

2015/d22.py

@@ -0,0 +1,64 @@
+from collections import deque
+
+min_mana_win = float("INF")
+enemy_damage = 9
+enemy_hit = 58
+player_mana = 500
+player_hit = 50
+
+states = deque()
+states.append((0, player_hit, player_mana, enemy_hit, 0, -1, -1, -1))
+seen = set()
+
+hard_mode = True
+
+while states:
+    s = states.popleft()
+    if s in seen:
+        continue
+    seen.add(s)
+    player_turn, player_hit, player_mana, enemy_hit, mana_used, shield_time, poison_time, charge_time = s
+
+    if enemy_hit <= 0:
+        if mana_used < min_mana_win:
+            min_mana_win = mana_used
+            print(min_mana_win)
+        continue
+
+    if hard_mode and player_turn == 0:
+        player_hit -= 1
+
+    if player_hit <= 0 or player_mana < 53 or mana_used > min_mana_win:
+        continue
+
+    if poison_time >= 0:
+        enemy_hit -= 3
+
+    if charge_time >= 0:
+        player_mana += 101
+
+    if charge_time < -1:
+        charge_time = -1
+    if poison_time < -1:
+        poison_time = -1
+    if shield_time < -1:
+        shield_time = -1
+
+    if player_turn == 0:
+        for a in ["magic", "drain", "shield", "poison", "recharge"]:
+            if a == "magic" and player_mana >= 53:
+                states.append((1, player_hit, player_mana - 53, enemy_hit - 4, mana_used + 53, shield_time - 1, poison_time - 1, charge_time - 1))
+            elif a == "drain" and player_mana >= 73:
+                states.append((1, player_hit + 2, player_mana - 73, enemy_hit - 2, mana_used + 73, shield_time - 1, poison_time - 1, charge_time - 1))
+            elif a == "shield" and player_mana >= 113 and shield_time <= 0:
+                states.append((1, player_hit, player_mana - 113, enemy_hit, mana_used + 113, 6 - 1, poison_time - 1, charge_time - 1))
+            elif a == "poison" and player_mana >= 173 and poison_time <= 0:
+                states.append((1, player_hit, player_mana - 173, enemy_hit, mana_used + 173, shield_time - 1, 6 - 1, charge_time - 1))
+            elif a == "recharge" and player_mana >= 229 and charge_time <= 0:
+                states.append((1, player_hit, player_mana - 229, enemy_hit, mana_used + 229, shield_time - 1, poison_time - 1, 5 - 1))
+    else:
+        if shield_time >= 0:
+            player_hit -= (enemy_damage - 7)
+        else:
+            player_hit -= enemy_damage
+        states.append((0, player_hit, player_mana, enemy_hit, mana_used, shield_time - 1, poison_time - 1, charge_time - 1))