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1 --- Day 14: Parabolic Reflector Dish ---
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2
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3 Given movable objects (O) and stationary objects (#) with free space (.),
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4 "tilt" the map to the top so that the movable objects slide to the top
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5 of the map and then determine the total "load" - the sum of the number
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6 of rows from the movable object to the bottom of the map.
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7
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8 Given:
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9
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10 O....#....
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11 O.OO#....#
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12 .....##...
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13 OO.#O....O
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14 .O.....O#.
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15 O.#..O.#.#
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16 ..O..#O..O
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17 .......O..
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18 #....###..
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19 #OO..#....
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20
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21 Sliding makes it:
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22
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23 OOOO.#.O..
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24 OO..#....#
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25 OO..O##..O
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26 O..#.OO...
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27 ........#.
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28 ..#....#.#
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29 ..O..#.O.O
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30 ..O.......
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31 #....###..
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32 #....#....
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33
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34 The load calculation is:
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35
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36 OOOO.#.O.. 10
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37 OO..#....# 9
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38 OO..O##..O 8
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39 O..#.OO... 7
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40 ........#. 6
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41 ..#....#.# 5
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42 ..O..#.O.O 4
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43 ..O....... 3
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44 #....###.. 2
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45 #....#.... 1
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46
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47 Which gives 136.
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48
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49 Given a huge map, what is the load?
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50
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51 --- Part 2 ---
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52
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53 Now we want to cycle them by shifting them all in a cycle north, west, south and east.
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54
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55 After 1 cycle:
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56 .....#....
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57 ....#...O#
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58 ...OO##...
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59 .OO#......
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60 .....OOO#.
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61 .O#...O#.#
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62 ....O#....
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63 ......OOOO
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64 #...O###..
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65 #..OO#....
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66
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67 After 2 cycles:
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68 .....#....
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69 ....#...O#
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70 .....##...
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71 ..O#......
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72 .....OOO#.
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73 .O#...O#.#
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74 ....O#...O
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75 .......OOO
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76 #..OO###..
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77 #.OOO#...O
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78
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79 After 3 cycles:
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80 .....#....
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81 ....#...O#
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82 .....##...
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83 ..O#......
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84 .....OOO#.
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85 .O#...O#.#
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86 ....O#...O
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87 .......OOO
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88 #...O###.O
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89 #.OOO#...O
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90
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91
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92 What is the top load after 1,000,000,000 cycles? |