53 lines
913 B
Go
53 lines
913 B
Go
package daythree
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import (
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"advent-of-code/internal/registry"
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"os"
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"strings"
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)
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func init() {
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registry.Register("2020D3", ParseInput, PartOne, PartTwo)
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}
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func ParseInput(filepath string) []string {
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content, _ := os.ReadFile(filepath)
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return strings.Split(string(content), "\n")
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}
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func PartOne(input []string) int {
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trees := 0
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column := 0
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for row := range input {
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if len(input[row]) == 0 {
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continue
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}
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if input[row][column%len(input[row])] == '#' {
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trees++
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}
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column += 3
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}
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return trees
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}
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func PartTwo(input []string) int {
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result := 1
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slopes := [][]int{{1, 1}, {3, 1}, {5, 1}, {7, 1}, {1, 2}}
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for _, slope := range slopes {
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trees := 0
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column := 0
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for row := 0; row < len(input); row += slope[1] {
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if len(input[row]) == 0 {
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continue
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}
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if input[row][column%len(input[row])] == '#' {
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trees++
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}
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column += slope[0]
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}
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result *= trees
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}
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return result
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}
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