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solved day 3

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Joshua Seigler 2020-12-03 00:14:03 -05:00
parent eb884ec643
commit 9db2a69230
2 changed files with 349 additions and 7 deletions
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33
solutions/day3/solution.js
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@ -4,20 +4,39 @@ const fromHere = position(__dirname)
const report = (...messages) => console.log(`[${require(fromHere('../../package.json')).logName} / ${__dirname.split(path.sep).pop()}]`, ...messages)
async function run () {
const input = (await read(fromHere('input.txt'), 'utf8')).trim()
const input = (await read(fromHere('input.txt'), 'utf8')).trim().split('\n')
await solveForFirstStar(input)
await solveForSecondStar(input)
}
async function solveForFirstStar (input) {
const solution = 'UNSOLVED'
// report('Input:', input);
report('Solution 1:', solution)
function slopeImpact (lines, delta) {
const width = lines[0].length
const pos = { x: 0, y: 0 }; let count = 0
while (pos.y < lines.length) {
if (lines[pos.y].charAt(pos.x) === '#') {
count++
}
pos.y += delta.y
pos.x += delta.x
pos.x %= width
}
return count
}
async function solveForSecondStar (input) {
const solution = 'UNSOLVED'
async function solveForFirstStar (lines) {
// report('lines:', lines);
report('Solution 1:', slopeImpact(lines, { x: 3, y: 1 }))
}
async function solveForSecondStar (lines) {
const solution = [
slopeImpact(lines, { x: 1, y: 1 }),
slopeImpact(lines, { x: 3, y: 1 }),
slopeImpact(lines, { x: 5, y: 1 }),
slopeImpact(lines, { x: 7, y: 1 }),
slopeImpact(lines, { x: 1, y: 2 })
].reduce((acc, cur) => acc * cur, 1)
report('Solution 2:', solution)
}