advent-of-code/day02/main.go
2023-12-08 21:30:49 -07:00

120 lines
2.2 KiB
Go

package main
import (
"bufio"
_ "embed"
"fmt"
"os"
"strconv"
"strings"
aoc "go.sour.is/advent-of-code-2023"
)
func main() {
result, err := aoc.Runner(run)
if err != nil {
aoc.Log("ERR", err)
os.Exit(1)
}
aoc.Log(result)
}
type result struct {
sum int
powerSum int
}
func (r result) String() string {
return fmt.Sprintln("result pt1:", r.sum, "\nresult pt2:", r.powerSum)
}
type gameResult struct {
red, green, blue int
}
func run(scan *bufio.Scanner) (*result, error) {
// only 12 red cubes, 13 green cubes, and 14 blue cubes
maxCounts := gameResult{
red: 12,
green: 13,
blue: 14,
}
games := [][]gameResult{}
games = append(games, []gameResult{})
for scan.Scan() {
pfx, text, ok := strings.Cut(scan.Text(), ":")
if !ok || !strings.HasPrefix(pfx, "Game") {
continue
}
games = append(games, []gameResult{})
for _, round := range strings.Split(text, ";") {
game := gameResult{}
for _, result := range strings.Split(round, ",") {
ns, color, _ := strings.Cut(strings.TrimSpace(result), " ")
n, err := strconv.Atoi(ns)
if err != nil {
panic(err)
}
switch color {
case "red":
game.red = n
case "green":
game.green = n
case "blue":
game.blue = n
}
}
games[len(games)-1] = append(games[len(games)-1], game)
}
}
aoc.Log(games)
aoc.Log(len(games))
sum := 0
powerSum := 0
for i, game := range games {
if i == 0 {
continue
}
mins := gameResult{}
ok := true
for _, round := range game {
mins.red = max(mins.red, round.red)
mins.green = max(mins.green, round.green)
mins.blue = max(mins.blue, round.blue)
if maxCounts.red < round.red {
aoc.Log("game", i, round, "too many red", round.red)
ok = false
} else if maxCounts.blue < round.blue {
aoc.Log("game", i, round, "too many blue", round.blue)
ok = false
} else if maxCounts.green < round.green {
aoc.Log("game", i, round, "too many green", round.green)
ok = false
}
aoc.Log("game", i, round, ok)
}
if ok {
sum += i
aoc.Log("game", i, "passes", sum)
}
power := mins.red * mins.blue * mins.green
aoc.Log("game", i, "mins", mins, power)
powerSum += power
}
return &result{sum, powerSum}, nil
}