day20

python/day20/bsp.txt

@@ -0,0 +1,7 @@
+1
+2
+-3
+3
+-2
+0
+4

python/day20/day20_1.py

@@ -0,0 +1,23 @@
+numbers = [int(i) for i in open("input.txt", "r").read().split()]
+idx = [i for i in range(len(numbers))]
+
+for i in range(len(idx)):
+    index = idx.index(i)
+    n = numbers[index]
+    if n == 0:
+        continue
+    new_index = index + n
+    if abs(new_index) > len(numbers) - 1:
+        new_index = new_index % (len(numbers) - 1)
+    if new_index == 0:
+        new_index = len(numbers) - 1
+    elif new_index == len(numbers) - 1:
+        new_index = 0
+    numbers.pop(index)
+    idx.pop(index)
+    numbers.insert(new_index, n)
+    idx.insert(new_index, i)
+
+rotated = numbers[numbers.index(0) :] + numbers[: numbers.index(0)]
+rest = [x % len(rotated) for x in [1000, 2000, 3000]]
+print(sum([rotated[r] for r in rest]))

python/day20/day20_2.py

@@ -0,0 +1,32 @@
+key = 811589153
+numbers = [int(i) * key for i in open("input.txt", "r").read().split()]
+idx = [i for i in range(len(numbers))]
+
+
+def mix(numbers, idx):
+    for i in range(len(idx)):
+        index = idx.index(i)
+        n = numbers[index]
+        if n == 0:
+            continue
+        new_index = index + n
+        if abs(new_index) > len(numbers) - 1:
+            new_index = new_index % (len(numbers) - 1)
+        if new_index == 0:
+            new_index = len(numbers) - 1
+        elif new_index == len(numbers) - 1:
+            new_index = 0
+        numbers.pop(index)
+        idx.pop(index)
+        numbers.insert(new_index, n)
+        idx.insert(new_index, i)
+    # idx = idx[numbers.index(0) :] + idx[: numbers.index(0)]
+    return numbers, idx
+
+
+for i in range(10):
+    numbers, idx = mix(numbers, idx)
+
+rotated = numbers[numbers.index(0) :] + numbers[: numbers.index(0)]
+rest = [x % len(rotated) for x in [1000, 2000, 3000]]
+print(sum([rotated[r] for r in rest]))