Solve 2016 day 1 to get rolling again.

2016/d1.py

@@ -0,0 +1,39 @@
+from lib import *
+
+EXAMPLE = "R5, L5, R5, R3"
+EXAMPLE = "R2, R2, R2"
+EXAMPLE = "R8, R4, R4, R8"
+
+DIRS = "NESW"
+MOVES = {
+    "N": (-1, 0),
+    "E": (0, 1),
+    "S": (1, 0),
+    "W": (0, -1),
+} 
+
+def solve(input: Input, second=False):
+    steps = input.text.split(", ")
+    coord, dir = (0, 0), "N"
+    allcoords = set([coord])
+    for step in steps:
+        turn, nsteps = step[0], int(step[1:])
+        os = -1 if turn == "L" else 1
+        dir = DIRS[(DIRS.index(dir) + os) % len(DIRS)]
+        rowo, colo = MOVES[dir]
+        if second:
+            for n in range(1, nsteps):
+                tcoord = (coord[0] + rowo * n, coord[1] + colo * n)
+                if tcoord in allcoords:
+                    return abs(tcoord[0]) + abs(tcoord[1])
+                allcoords.add(tcoord)
+        coord = (coord[0] + rowo * nsteps, coord[1] + colo * nsteps)
+    return abs(coord[0]) + abs(coord[1])
+
+def main():
+    DAY_INPUT = "i1.txt"
+    print("Solution 1:", solve(Input(DAY_INPUT)))
+    print("Solution 2:", solve(Input(DAY_INPUT), True))
+
+if __name__ == "__main__":
+    main()

2016/lib.py

@@ -0,0 +1 @@
+../lib.py

README.md

@@ -24,4 +24,11 @@ written in Python.
 - Day 17: 9:05
 - Day 18: 10:39
 - Day 19:
-- Day 20: 
+- Day 20: 10:54
+- Day 21: 25:52 cute bug where I didn't consider that no armor is an option
+- Day 22: That was bad. Did not know how to choose between dfs/bfs and logic errors.
+- Day 23: 
+
+# 2016
+
+- Day 1: 29:00 That was emberassingly slow. Out of my rhythm?