44 lines
897 B
Go
44 lines
897 B
Go
package main
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import (
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"bytes"
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"fmt"
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"os"
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h "git.bullercodeworks.com/brian/adventofcode/helpers"
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)
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func main() {
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if len(os.Args) < 3 {
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fmt.Println("Usage: ./day18 <filename> <numrows>")
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}
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input := h.FileToBytes(os.Args[1])
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numRows := h.Atoi(os.Args[2])
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room := [][]byte{input}
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for row := 1; row < numRows; row++ {
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room = append(room, []byte{})
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for tile := 0; tile < len(room[0])-1; tile++ {
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var l, r byte
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switch tile {
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case 0:
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l, r = '.', room[row-1][tile+1]
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case len(input) - 2:
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l, r = room[row-1][tile-1], '.'
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default:
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l, r = room[row-1][tile-1], room[row-1][tile+1]
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}
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if l != r && (l == '^' || r == '^') {
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room[row] = append(room[row], '^')
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} else {
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room[row] = append(room[row], '.')
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}
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}
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}
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var safeCount int
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for i := range room {
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safeCount += bytes.Count(room[i], []byte{'.'})
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}
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fmt.Println(safeCount, "safe tiles")
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}
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