53 lines
1.5 KiB
Markdown
53 lines
1.5 KiB
Markdown
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## \-\-- Day 11: Hex Ed \-\--
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Crossing the bridge, you\'ve barely reached the other side of the stream
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when a program comes up to you, clearly in distress. \"It\'s my child
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process,\" she says, \"he\'s gotten lost in an infinite grid!\"
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Fortunately for her, you have plenty of experience with infinite grids.
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Unfortunately for you, it\'s a [hex
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grid](https://en.wikipedia.org/wiki/Hexagonal_tiling).
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The hexagons (\"hexes\") in [this
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grid]{title="Raindrops on roses and whiskers on kittens."} are aligned
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such that adjacent hexes can be found to the north, northeast,
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southeast, south, southwest, and northwest:
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\ n /
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nw +--+ ne
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/ \
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-+ +-
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\ /
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sw +--+ se
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/ s \
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You have the path the child process took. Starting where he started, you
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need to determine the fewest number of steps required to reach him. (A
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\"step\" means to move from the hex you are in to any adjacent hex.)
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For example:
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- `ne,ne,ne` is `3` steps away.
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- `ne,ne,sw,sw` is `0` steps away (back where you started).
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- `ne,ne,s,s` is `2` steps away (`se,se`).
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- `se,sw,se,sw,sw` is `3` steps away (`s,s,sw`).
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Your puzzle answer was `675`.
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## \-\-- Part Two \-\-- {#part2}
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*How many steps away* is the *furthest* he ever got from his starting
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position?
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Your puzzle answer was `1424`.
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Both parts of this puzzle are complete! They provide two gold stars:
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\*\*
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At this point, you should [return to your Advent calendar](/2017) and
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try another puzzle.
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If you still want to see it, you can [get your puzzle
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input](11/input).
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