26 lines
811 B
TypeScript
26 lines
811 B
TypeScript
import { open } from 'node:fs/promises';
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function computeDifference(input: number[]) {
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const output: number[] = []
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input.forEach((e, i, arr) => {
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if (i === 0) return
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output.push(arr[i] - arr[i - 1])
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});
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return output
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}
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const file = await open('./inputs/9');
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let sum = 0
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for await (const line of file.readLines()) {
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const numbers = line.split(" ").map<number>(e => Number(e))
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const differences: number[][] = [numbers]
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if (differences.at(-1) === undefined) throw new Error('wtf')
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while (!differences.at(-1)?.every(e => e === 0)) {
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differences.push(computeDifference(differences.at(-1)!))
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}
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let acc = differences.reduceRight((prev, cur) => {
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cur.push(cur.at(-1)! + prev)
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return cur.at(-1)!
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}, 0)
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sum += acc
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}
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console.log(sum) |