From bf0aa772604e24573715518800e1a4b5db2f7a78 Mon Sep 17 00:00:00 2001
From: Luke Hubmayer-Werner <mongoose41@gmail.com>
Date: Fri, 7 Dec 2018 16:19:15 +1030
Subject: [PATCH] 2018 Day 7

---
 2018/day7-input | 101 ++++++++++++++++++++++++++++++++++++++++++++++++
 2018/day7.py    |  73 ++++++++++++++++++++++++++++++++++
 2 files changed, 174 insertions(+)
 create mode 100644 2018/day7-input
 create mode 100644 2018/day7.py

diff --git a/2018/day7-input b/2018/day7-input
new file mode 100644
index 0000000..41e50b9
--- /dev/null
+++ b/2018/day7-input
@@ -0,0 +1,101 @@
+Step C must be finished before step P can begin.
+Step V must be finished before step Q can begin.
+Step T must be finished before step X can begin.
+Step B must be finished before step U can begin.
+Step Z must be finished before step O can begin.
+Step P must be finished before step I can begin.
+Step D must be finished before step G can begin.
+Step A must be finished before step Y can begin.
+Step R must be finished before step O can begin.
+Step J must be finished before step E can begin.
+Step N must be finished before step S can begin.
+Step X must be finished before step H can begin.
+Step F must be finished before step L can begin.
+Step S must be finished before step I can begin.
+Step W must be finished before step Q can begin.
+Step H must be finished before step K can begin.
+Step K must be finished before step Q can begin.
+Step E must be finished before step L can begin.
+Step Q must be finished before step O can begin.
+Step U must be finished before step G can begin.
+Step L must be finished before step O can begin.
+Step Y must be finished before step G can begin.
+Step G must be finished before step I can begin.
+Step M must be finished before step I can begin.
+Step I must be finished before step O can begin.
+Step A must be finished before step N can begin.
+Step H must be finished before step O can begin.
+Step T must be finished before step O can begin.
+Step H must be finished before step U can begin.
+Step A must be finished before step I can begin.
+Step B must be finished before step R can begin.
+Step V must be finished before step T can begin.
+Step H must be finished before step M can begin.
+Step C must be finished before step A can begin.
+Step B must be finished before step G can begin.
+Step L must be finished before step Y can begin.
+Step T must be finished before step J can begin.
+Step A must be finished before step R can begin.
+Step X must be finished before step L can begin.
+Step B must be finished before step L can begin.
+Step A must be finished before step F can begin.
+Step K must be finished before step O can begin.
+Step W must be finished before step M can begin.
+Step Z must be finished before step N can begin.
+Step Z must be finished before step S can begin.
+Step R must be finished before step K can begin.
+Step Q must be finished before step L can begin.
+Step G must be finished before step O can begin.
+Step F must be finished before step Y can begin.
+Step V must be finished before step H can begin.
+Step E must be finished before step I can begin.
+Step W must be finished before step Y can begin.
+Step U must be finished before step I can begin.
+Step F must be finished before step K can begin.
+Step M must be finished before step O can begin.
+Step Z must be finished before step H can begin.
+Step X must be finished before step S can begin.
+Step J must be finished before step O can begin.
+Step B must be finished before step I can begin.
+Step F must be finished before step H can begin.
+Step D must be finished before step U can begin.
+Step E must be finished before step M can begin.
+Step Z must be finished before step X can begin.
+Step P must be finished before step L can begin.
+Step W must be finished before step H can begin.
+Step C must be finished before step D can begin.
+Step A must be finished before step X can begin.
+Step Q must be finished before step I can begin.
+Step R must be finished before step Y can begin.
+Step B must be finished before step A can begin.
+Step N must be finished before step L can begin.
+Step H must be finished before step G can begin.
+Step Y must be finished before step M can begin.
+Step L must be finished before step G can begin.
+Step G must be finished before step M can begin.
+Step Z must be finished before step R can begin.
+Step S must be finished before step Q can begin.
+Step P must be finished before step J can begin.
+Step V must be finished before step J can begin.
+Step J must be finished before step I can begin.
+Step J must be finished before step X can begin.
+Step W must be finished before step O can begin.
+Step B must be finished before step F can begin.
+Step R must be finished before step M can begin.
+Step V must be finished before step S can begin.
+Step H must be finished before step E can begin.
+Step E must be finished before step U can begin.
+Step R must be finished before step W can begin.
+Step X must be finished before step Q can begin.
+Step N must be finished before step G can begin.
+Step T must be finished before step I can begin.
+Step L must be finished before step M can begin.
+Step H must be finished before step I can begin.
+Step U must be finished before step M can begin.
+Step C must be finished before step H can begin.
+Step P must be finished before step H can begin.
+Step J must be finished before step F can begin.
+Step A must be finished before step O can begin.
+Step X must be finished before step M can begin.
+Step H must be finished before step L can begin.
+Step W must be finished before step K can begin.
diff --git a/2018/day7.py b/2018/day7.py
new file mode 100644
index 0000000..39624e6
--- /dev/null
+++ b/2018/day7.py
@@ -0,0 +1,73 @@
+with open('day7-input', 'r') as file:
+  data = [l.strip('\n') for l in file]
+
+steps = set()
+step_deps = {}
+for line in data:
+  s = line.split()
+  step1 = s[1]
+  step2 = s[-3]
+  steps.add(step1)
+  steps.add(step2)
+  if step2 in step_deps:
+    step_deps[step2] += step1
+  else:
+    step_deps[step2] = [step1]
+
+queue = [step for step in steps]
+step_deps_1 = step_deps.copy()
+completed_steps = set()
+ready_steps = set()
+output = []
+while queue:
+  for step in queue:
+    if step not in step_deps_1:
+      ready_steps.add(step)
+    else:
+      deps = [d for d in step_deps_1[step] if d not in completed_steps]
+      if len(deps) > 0:
+        step_deps_1[step] = deps
+      else:
+        ready_steps.add(step)
+        step_deps_1.pop(step)
+  for step in sorted(ready_steps)[:1]:
+    completed_steps.add(step)
+    output += step
+    queue.remove(step)
+    break
+  ready_steps = set()
+print(''.join(output))  # Part 1
+
+unprocessed_steps = steps.copy()
+step_deps_2 = step_deps.copy()
+completed_steps_2 = set()
+ready_steps_2 = set()
+waiting_steps = {}
+time = 0
+while unprocessed_steps:
+  for k in list(waiting_steps.keys()):
+    waiting_steps[k] -= 1
+    if waiting_steps[k] < 1:
+      completed_steps_2.add(k)
+      print(f'{time:04}: Step {k} complete!')  # Debug
+      waiting_steps.pop(k)
+  for step in unprocessed_steps-ready_steps_2:
+    if step not in step_deps_2:
+      ready_steps_2.add(step)
+    else:
+      deps = [d for d in step_deps_2[step] if d not in completed_steps_2]
+      if len(deps) > 0:
+        step_deps_2[step] = deps
+      else:
+        ready_steps_2.add(step)
+        step_deps_2.pop(step)
+  for step in list(sorted(ready_steps_2)):
+    if len(waiting_steps) >= 5:  # Only 5 workers
+      break
+    waiting_steps[step] = 60 + ord(step)-64
+    print(f'{time:04}: Starting step {step}! ({waiting_steps[step]} seconds remain)')  # Debug
+    unprocessed_steps.remove(step)
+    ready_steps_2.remove(step)
+  time += 1
+time += max(waiting_steps.values()) - 1  # t got moved forward 1 at end of while loop
+print(time)  # Part 2