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Fil
Vocateur.
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Advent of Code
Edited
Dec 6, 2023
1 fork
2 stars
Advent of Code
Advent of Code 2024 - #1Advent of Code 2023 - #19Advent of Code 2023 - #18Advent of Code 2023 - #17Advent of Code 2023 - #16Advent of Code 2023 - #15Advent of Code 2023 - #14Advent of Code 2023 - #13Advent of Code 2023 - #12Advent of Code 2023 - #11Advent of Code 2023 - #10Advent of Code 2023 - #9Advent of Code 2023 - #8Advent of Code 2023 - #7
Advent of Code 2023 - #6
Advent of Code 2023 - #5Advent of Code 2023 - #4Advent of Code 2023 - #3Advent of Code 2023 - #2Advent of Code 2023 - #1
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input = `Time: 62 73 75 65
Distance: 644 1023 1240 1023`
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races = [[62, 644], [73, 1023], [75, 1240], [65, 1023]]
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answer1 = races.map(ways).reduce((a, b) => a * b, 1)
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function ways([time, record]) {
const span = Math.sqrt((time / 2) ** 2 - record);
// d3.sum(d3.range(time + 1), (i) => Math.abs(i - time / 2) < span); // first approach, lame
return Math.ceil(time / 2 + span) - Math.floor(time / 2 - span) - 1; // better
}
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ways([7, 9])
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ways([15, 40])
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ways([30, 200])
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race2 = [
+races.map((d) => String(d[0])).join(""),
+races.map((d) => String(d[1])).join("")
]
Insert cell
ways(race2)
Insert cell

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