day3.ipynb

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  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "def parseInput():\n",
    "    filepath = 'day3_input'\n",
    "    data = []\n",
    "    with open(filepath) as file:\n",
    "        data = [line.rstrip() for line in file]\n",
    "    return data"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "wires = parseInput()\n",
    "rightWireParts = wires[0].split(',')\n",
    "leftWireParts = wires[1].split(',')\n",
    "\n",
    "rightCurPart = leftCurPart = -1\n",
    "rightCurPartLength = leftCurPartLength = -1\n",
    "rightCurDirection = leftCurDirection = False\n",
    "rightCurPartIndex = leftCurPartIndex = 0\n",
    "rightCoord = [0,0]\n",
    "leftCoord = [0,0]\n",
    "\n",
    "raceTrack = {}\n",
    "raceTrack[0,0] = 'O'\n",
    "\n",
    "foundCrossings = {}\n",
    "\n",
    "for ticks in range (0,138225):\n",
    "    \n",
    "    if not rightCurDirection:\n",
    "        rightCurPart += 1\n",
    "        rightCurDirection = rightWireParts[rightCurPart][0]\n",
    "        rightCurPartLength = int(rightWireParts[rightCurPart][1:])\n",
    "        rightCurPartIndex = 0\n",
    "        \n",
    "    if not leftCurDirection:\n",
    "        leftCurPart += 1\n",
    "        leftCurDirection  = leftWireParts[leftCurPart][0]\n",
    "        leftCurPartLength = int(leftWireParts[leftCurPart][1:])\n",
    "        leftCurPartIndex = 0\n",
    "        \n",
    "        \n",
    "    if   rightCurDirection == 'U':\n",
    "        rightCoord[1] -= 1\n",
    "    elif rightCurDirection == 'R':\n",
    "        rightCoord[0] += 1\n",
    "    elif rightCurDirection == 'D':\n",
    "        rightCoord[1] += 1\n",
    "    elif rightCurDirection == 'L':\n",
    "        rightCoord[0] -= 1\n",
    "    \n",
    "    if (rightCoord[0],rightCoord[1]) in raceTrack and raceTrack[rightCoord[0],rightCoord[1]] == 'L':\n",
    "        foundCrossings[rightCoord[0],rightCoord[1]] = ticks\n",
    "        \n",
    "    raceTrack[rightCoord[0],rightCoord[1]] = 'R'\n",
    "    \n",
    "    rightCurPartIndex += 1\n",
    "    if rightCurPartIndex == rightCurPartLength:\n",
    "        rightCurDirection = False\n",
    "        \n",
    "        \n",
    "    if   leftCurDirection == 'U':\n",
    "        leftCoord[1] -= 1\n",
    "    elif leftCurDirection == 'R':\n",
    "        leftCoord[0] += 1\n",
    "    elif leftCurDirection == 'D':\n",
    "        leftCoord[1] += 1\n",
    "    elif leftCurDirection == 'L':\n",
    "        leftCoord[0] -= 1\n",
    "    \n",
    "    if (leftCoord[0],leftCoord[1]) in raceTrack and raceTrack[leftCoord[0],leftCoord[1]] == 'R':\n",
    "        foundCrossings[leftCoord[0],leftCoord[1]] = ticks\n",
    "    \n",
    "    raceTrack[leftCoord[0],leftCoord[1]] = 'L'\n",
    "        \n",
    "    leftCurPartIndex += 1\n",
    "    if leftCurPartIndex == leftCurPartLength:\n",
    "        leftCurDirection = False\n",
    "        \n",
    "print(foundCrossings)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "rightCurPart = leftCurPart = -1\n",
    "rightCurPartLength = leftCurPartLength = -1\n",
    "rightCurDirection = leftCurDirection = False\n",
    "rightCurPartIndex = leftCurPartIndex = 0\n",
    "rightCoord = [0,0]\n",
    "leftCoord = [0,0]\n",
    "\n",
    "raceTrack = {}\n",
    "raceTrack[0,0] = 'O'\n",
    "\n",
    "visitedCrossings = {}\n",
    "print(foundCrossings)\n",
    "\n",
    "for ticks in range (0,138225):\n",
    "    \n",
    "    if not rightCurDirection:\n",
    "        rightCurPart += 1\n",
    "        rightCurDirection = rightWireParts[rightCurPart][0]\n",
    "        rightCurPartLength = int(rightWireParts[rightCurPart][1:])\n",
    "        rightCurPartIndex = 0\n",
    "        \n",
    "        \n",
    "    if   rightCurDirection == 'U':\n",
    "        rightCoord[1] -= 1\n",
    "    elif rightCurDirection == 'R':\n",
    "        rightCoord[0] += 1\n",
    "    elif rightCurDirection == 'D':\n",
    "        rightCoord[1] += 1\n",
    "    elif rightCurDirection == 'L':\n",
    "        rightCoord[0] -= 1\n",
    "    \n",
    "    if (rightCoord[0],rightCoord[1]) in foundCrossings and not (rightCoord[0],rightCoord[1]) in visitedCrossings:\n",
    "        visitedCrossings[rightCoord[0],rightCoord[1]] = ticks\n",
    "        foundCrossings[rightCoord[0],rightCoord[1]] += ticks + 2 # account for start and crossing\n",
    "        \n",
    "    raceTrack[rightCoord[0],rightCoord[1]] = 'R'\n",
    "    \n",
    "    rightCurPartIndex += 1\n",
    "    if rightCurPartIndex == rightCurPartLength:\n",
    "        rightCurDirection = False\n",
    "\n",
    "        \n",
    "print(foundCrossings)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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