Day 6 part 2

6/6_2.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python
+# 2021 - Advent Of Code - 6 part 2
+
+def parse_file(file):
+    with open(file) as f:
+        line = f.readline()
+
+    list_state = [int(x) for x in line.split(',')]
+
+    state = dict(zip(range(0, 9), [0]*9))
+    for c in range(0, 9):
+        state[c] = list_state.count(c)
+
+    return state
+
+
+def iterate(state):
+    new_fish = state[0]
+    state[0] = state[1]
+    state[1] = state[2]
+    state[2] = state[3]
+    state[3] = state[4]
+    state[4] = state[5]
+    state[5] = state[6]
+    state[6] = state[7] + new_fish
+    state[7] = state[8]
+    state[8] = new_fish
+
+
+# init_state = parse_file('input_example.txt')
+init_state = parse_file('input.txt')
+print(f'Initial state: {init_state}')
+
+DAYS = 256
+
+for d in range(DAYS):
+    iterate(init_state)
+
+lanternfish = 0
+for k, v in init_state.items():
+    lanternfish += v
+
+print(f'There\'s {lanternfish} lanternfish after {DAYS} days')