34 lines
1021 B
TypeScript
34 lines
1021 B
TypeScript
import { sumArray } from '../../utils/array.ts';
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import { type Coordinate, isInteger } from '../../utils/coordinates.ts';
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function findIntersection(input: string, offset: number = 0) {
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const match = input.matchAll(
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/^Button A: X\+(\d*), Y\+(\d*)\nButton B: X\+(\d*), Y\+(\d*)\nPrize: X=(\d*), Y=(\d*)$/gm
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);
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const matches = Array.from(match, (m) => ({
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a: [m[1], m[2]].map(Number),
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b: [m[3], m[4]].map(Number),
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price: [m[5], m[6]].map((n) => Number(n) + offset)
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}));
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const intersection = matches
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.map(
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({ a: [a1, a2], b: [b1, b2], price: [p1, p2] }) =>
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[
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(b1 * -p2 - b2 * -p1) / (a1 * b2 - a2 * b1),
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(-p1 * a2 - -p2 * a1) / (a1 * b2 - a2 * b1)
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] as Coordinate
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)
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.filter(isInteger);
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return sumArray(intersection.map(([a, b]) => 3 * a + b));
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}
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export function solveFirst(input: string): number {
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return findIntersection(input);
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}
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export function solveSecond(input: string): number {
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return findIntersection(input, 10000000000000);
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}
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