aoc2023/day-18/two.go

package main

import (
	"strings"
)

func fromHex(imager *imager, lines []string) {
	for _, line := range lines {
		direction, count := func() (string, int) {
			var dirs = []string{"R", "D", "L", "U"}
			m := getParams(r, line)
			code := strings.TrimLeft(m["colour"], "#")
			return dirs[mustConv(string(code[len(code)-1]))], mustConvHex(code[:len(code)-1])
		}()
		imager.add(direction, count)
	}
}

// two returns the area of the polygon described by imager.space
// it uses the hex codes to define points
func two(lines []string) int {
	imager := newImager()
	buildImage(fromHex, imager, lines)

	return calculateArea(imager.space)
}