Add 2017 Day 17

2017/Day 17 - 1.py

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+import collections
+
+
+with open('Day 17 - input', 'r') as f:
+    data = f.readlines()
+
+steps = int(data[0])
+circular_buffer = collections.deque([0])
+insertion_count = 2017
+
+for i in range(1, insertion_count + 1):
+    # rotate buffer steps modulo current length
+    circular_buffer.rotate(-steps % i)
+    # append new value
+    circular_buffer.append(i)
+
+# solution is first value in buffer
+print(f"The value after {insertion_count} is {circular_buffer[0]}")

2017/Day 17 - 2.py

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+import collections
+
+
+with open('Day 17 - input', 'r') as f:
+    data = f.readlines()
+
+steps = int(data[0])
+
+circular_buffer = collections.deque([0])
+insertion_count = 5000000
+offset = 0
+
+for i in range(1, insertion_count + 1):
+    # rotate buffer steps modulo current length
+    spin = -steps % i
+    circular_buffer.rotate(spin)
+    # append new value
+    circular_buffer.append(i)
+    # keep track of cummulative rotation
+    offset = (offset + spin) % i
+
+# roll back to get value after 0
+circular_buffer.rotate(-offset - 1)
+print(f"The value after 0 the moment {insertion_count} is inserted: {circular_buffer[0]}")