Added 2019 day 06

2019/06/code.py

@@ -0,0 +1,61 @@
+""" https://adventofcode.com/2019/day/6 """
+
+def readFile():
+    with open(f"{__file__.rstrip('code.py')}input.txt", "r") as f:
+        return [data[:-1].split(")") for data in f.readlines()]
+
+def parse(lines):
+    data = {}
+    for line in lines:
+        data[line[1]] = line[0]
+    return data
+
+def countOrbits(data, node):
+    if node not in data:
+        return 0
+    return 1 + countOrbits(data, data[node])
+
+def getIntersection(data, node1, node2):
+    node = node1
+    parents = []
+
+    while data[node] in data:
+        parents.append(data[node])
+        node = data[node]
+    parents.append(data[node])
+
+    node = node2
+    while node not in parents:
+        node = data[node]
+    
+    return node
+
+def getJumps(data, start, goal, intersection):
+    iDist = countOrbits(data, intersection)
+    return countOrbits(data, start) + countOrbits(data, goal) - 2*iDist - 2
+
+def part1(vals : list):
+    return sum([countOrbits(vals, val) for val in vals])
+
+def part2(vals : list):
+    intersection = getIntersection(vals, "YOU", "SAN")
+    return getJumps(vals, "YOU", "SAN", intersection)
+
+def test():
+    lines = [["COM","B"],["B","C"],["C","D"],["D","E"],["E","F"],
+        ["B","G"],["G","H"],["D","I"],["E","J"],["J","K"],["K","L"]]
+    vals = parse(lines)
+    assert countOrbits(vals, "D") == 3
+    assert countOrbits(vals, "L") == 7
+    assert countOrbits(vals, "COM") == 0
+    assert sum([countOrbits(vals, val) for val in vals]) == 42
+    vals["YOU"] = "K"
+    vals["SAN"] = "I"
+    assert getIntersection(vals, "YOU", "SAN") == "D"
+    assert getJumps(vals, "YOU", "SAN", "D") == 4
+
+if __name__ == "__main__":
+    test()
+    vals = parse(readFile())
+    print(f"Part 1: {part1(vals)}")
+    print(f"Part 2: {part2(vals)}")