45 lines
779 B
Go
45 lines
779 B
Go
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package main
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import (
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"fmt"
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"os"
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"git.annabunch.es/annabunches/adventofcode/2020/lib/fileutils"
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)
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func countTrees(input []string, right, down int) int {
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x := 0
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total := 0
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for y, line := range input {
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if y == 0 || len(line) == 0 || y%down != 0 {
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continue
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}
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x = (x + right) % len(line)
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if line[x] == '#' {
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total += 1
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}
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}
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return total
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}
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func main() {
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step := os.Args[1]
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values := fileutils.InputParserStrings(os.Args[2])
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switch step {
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case "1":
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total := countTrees(values, 3, 1)
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fmt.Println("Trees:", total)
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case "2":
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total := countTrees(values, 1, 1)
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total *= countTrees(values, 3, 1)
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total *= countTrees(values, 5, 1)
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total *= countTrees(values, 7, 1)
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total *= countTrees(values, 1, 2)
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fmt.Println("Tree Product:", total)
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}
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}
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