112 lines
2.0 KiB
Go
112 lines
2.0 KiB
Go
package main
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import (
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"bufio"
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"fmt"
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"os"
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"strconv"
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"strings"
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"time"
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)
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func main() {
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start := time.Now()
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partOne()
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duration := time.Since(start)
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partTwo()
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duration2 := time.Since(start)
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fmt.Printf("p1: %s, p2: %s\n", duration, duration2-duration)
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}
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func makeScanner(test bool) *bufio.Scanner {
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var f *os.File
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if test {
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f, _ = os.Open("inputs/testinput")
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} else {
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f, _ = os.Open("inputs/input")
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}
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reader := bufio.NewReader(f)
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return bufio.NewScanner(reader)
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}
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func mustAtoi(line string) int {
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i, _ := strconv.Atoi(line)
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return i
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}
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func fuelCostPartOne(crabs []int, column int) int {
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var totalFuel int
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for _, v := range crabs {
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if column < v {
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totalFuel += v - column
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}
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if column > v {
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totalFuel += column - v
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}
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}
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return totalFuel
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}
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func fuelCostPartTwo(crabs []int, column int) int {
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var totalFuel int
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for _, v := range crabs {
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if column < v {
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totalFuel += ((v - column) * ((v - column) + 1)) / 2
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}
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if column > v {
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totalFuel += ((column - v) * ((column - v) + 1)) / 2
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}
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}
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return totalFuel
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}
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func partOne() {
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scanner := makeScanner(false)
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// just a single line today
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scanner.Scan()
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input := strings.Split(scanner.Text(), ",")
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crabs := []int{}
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var max int
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for _, v := range input {
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crab := mustAtoi(v)
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crabs = append(crabs, crab)
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if max < crab {
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max = crab
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}
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}
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lowestFuel := 1000000000 // some initial awful max fuel cost
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for i := 0; i <= max; i++ {
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cost := fuelCostPartOne(crabs, i)
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if cost < lowestFuel {
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lowestFuel = cost
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}
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}
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fmt.Println(lowestFuel)
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}
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func partTwo() {
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scanner := makeScanner(false)
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// just a single line today
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scanner.Scan()
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input := strings.Split(scanner.Text(), ",")
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crabs := []int{}
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var max int
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for _, v := range input {
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crab := mustAtoi(v)
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crabs = append(crabs, crab)
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if max < crab {
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max = crab
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}
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}
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lowestFuel := 1000000000 // some initial awful max fuel cost
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for i := 0; i <= max; i++ {
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cost := fuelCostPartTwo(crabs, i)
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if cost < lowestFuel {
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lowestFuel = cost
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}
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}
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fmt.Println(lowestFuel)
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}
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