adventofcode2023/main.go

package main

import (
	"flag"
	"fmt"
	"io"
	"log"
	"os"
	"strconv"
)

type puzzle interface {
	solve1(r io.Reader) string
	solve2(r io.Reader) string
}

var (
	// pick which day to run with a flag
	day = flag.String("d", "", "which day to solve")

	// slice of all puzzles
	puzzles = []puzzle{
		&day01{},
		&day02{},
		&day03{},
		&day04{},
		&day05{},
		&day06{},
		&day07{},
		&day08{},
		&day09{},
	}
)

func main() {
	flag.Parse()
	puzzleIndex, err := strconv.Atoi(*day)
	if err != nil {
		log.Fatalf("invalid puzzle day: %s", *day)
	}

	puzzle := puzzles[puzzleIndex-1]

	path1 := fmt.Sprintf("input/%d-1", puzzleIndex)
	path2 := fmt.Sprintf("input/%d-2", puzzleIndex)

	f1, err := os.Open(path1)
	if err == nil {
		fmt.Fprintf(os.Stdout, "Solution 1:\n%s\n", puzzle.solve1(f1))
	}
	f2, err := os.Open(path2)
	if err == nil {
		fmt.Fprintf(os.Stdout, "Solution 2:\n%s\n", puzzle.solve2(f2))
	}
}