44 lines
1.6 KiB
TypeScript
44 lines
1.6 KiB
TypeScript
|
import fs from "fs";
|
||
|
|
|
||
|
|
export class Oasis {
|
||
|
|
private readonly sequences: number[][];
|
||
|
|
|
||
|
|
constructor(input: string) {
|
||
|
|
this.sequences = input.split('\n').map(line => line.split(' ').map(Number));
|
||
|
|
}
|
||
|
|
|
||
|
|
public getNextValueInSequence(seq: number[]): number {
|
||
|
|
if (new Set(seq).size === 1) return seq[0];
|
||
|
|
const differences = seq.reduce((acc: number[], curr, i, arr) => {
|
||
|
|
if (i === 0) return acc;
|
||
|
|
acc.push(curr - arr[i - 1]);
|
||
|
|
return acc;
|
||
|
|
}, []);
|
||
|
|
return this.getNextValueInSequence(differences) + seq[seq.length - 1];
|
||
|
|
}
|
||
|
|
|
||
|
|
public getPreviousValueInSequence(seq: number[]): number {
|
||
|
|
if (new Set(seq).size === 1) return seq[0];
|
||
|
|
const differences = seq.reduce((acc: number[], curr, i, arr) => {
|
||
|
|
if (i === 0) return acc;
|
||
|
|
acc.push(curr - arr[i - 1]);
|
||
|
|
return acc;
|
||
|
|
}, []);
|
||
|
|
return seq[0] - this.getPreviousValueInSequence(differences);
|
||
|
|
}
|
||
|
|
|
||
|
|
public getTotalOfNextValuesInSequences(): number {
|
||
|
|
return this.sequences.reduce((acc, curr) => acc + this.getNextValueInSequence(curr), 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
public getTotalOfPreviousValuesInSequences(): number {
|
||
|
|
return this.sequences.reduce((acc, curr) => acc + this.getPreviousValueInSequence(curr), 0);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
export const runDayNine = () => {
|
||
|
|
const input = fs.readFileSync('./inputs/day_nine_input.txt', 'utf-8').trimEnd();
|
||
|
|
const oasis = new Oasis(input);
|
||
|
|
console.log(oasis.getTotalOfNextValuesInSequences());
|
||
|
|
console.log(oasis.getTotalOfPreviousValuesInSequences());
|
||
|
|
}
|