mirror of
https://github.com/Luzifer/aoc2019.git
synced 2024-12-22 22:11:16 +00:00
60 lines
1.2 KiB
Go
60 lines
1.2 KiB
Go
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package aoc2019
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import (
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"bufio"
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"os"
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"strconv"
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"github.com/pkg/errors"
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)
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func calculateDay1FuelForMass(mass int64) int64 {
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return mass/3 - 2
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}
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func calculateDay1FuelForMassRecurse(mass int64) int64 {
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sumFuel := mass/3 - 2
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var addFuel = calculateDay1FuelForMass(sumFuel)
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for addFuel > 0 {
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sumFuel += addFuel
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addFuel = calculateDay1FuelForMass(addFuel)
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}
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return sumFuel
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}
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func solveDay1FromInput(inFile string, sumFn func(int64) int64) (int64, error) {
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f, err := os.Open(inFile)
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if err != nil {
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return 0, errors.Wrap(err, "Unable to open input file")
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}
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defer f.Close()
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var sumFuel int64
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scanner := bufio.NewScanner(f)
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for scanner.Scan() {
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if scanner.Err() != nil {
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return 0, errors.Wrap(err, "Unable to scan file")
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}
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mass, err := strconv.ParseInt(scanner.Text(), 10, 64)
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if err != nil {
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return 0, errors.Wrapf(err, "Unable to parse integer input %q", scanner.Text())
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}
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sumFuel += sumFn(mass)
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}
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return sumFuel, nil
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}
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func solveDay1Part1(inFile string) (int64, error) {
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return solveDay1FromInput(inFile, calculateDay1FuelForMass)
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}
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func solveDay1Part2(inFile string) (int64, error) {
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return solveDay1FromInput(inFile, calculateDay1FuelForMassRecurse)
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}
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