https://adventofcode.com/2020/day/4

passport_checker.go

package main

import (
	"io/ioutil"
	"strings"
)

func main() {
	bytes, _ := ioutil.ReadFile("./input.txt")
	input := strings.TrimRight(string(bytes), "\n")

	m := map[string]bool{
		"byr": false,
		"iyr": false,
		"eyr": false,
		"hgt": false,
		"hcl": false,
		"ecl": false,
		"pid": false,
		"cid": false,
	}

	validCount := 0

	for _, row := range strings.Split(input, "\n\n") {
		for _, f := range strings.Fields(row) {
			a := strings.Split(f, ":")[0]
			m[a] = true
		}

		allTrue := true
		for k, v := range m {
			if !v && k != "cid" {
				allTrue = false
			}
			m[k] = false
		}
		if allTrue {
			validCount++
		}
	}

	println(validCount)
}

strict_passport_checker.go

package main

import (
	"io/ioutil"
	"regexp"
	"strconv"
	"strings"
)

func main() {
	bytes, _ := ioutil.ReadFile("./input.txt")
	input := strings.TrimRight(string(bytes), "\n")

	m := map[string]bool{
		"byr": false,
		"iyr": false,
		"eyr": false,
		"hgt": false,
		"hcl": false,
		"ecl": false,
		"pid": false,
		"cid": false,
	}

	validCount := 0

	for _, row := range strings.Split(input, "\n\n") {
		println("================================")
		for _, f := range strings.Fields(row) {
			kv := strings.Split(f, ":")
			println(kv[0], kv[1], validate(kv[0], kv[1]))
			m[kv[0]] = validate(kv[0], kv[1])
		}

		allTrue := true
		for k, v := range m {
			if !v && k != "cid" {
				allTrue = false
			}
			m[k] = false
		}
		if allTrue {
			validCount++
		}
		println("allTrue", allTrue)
	}

	println(validCount)
}

func validate(key, value string) bool {
	switch key {
	case "byr":
		byr, err := strconv.Atoi(value)
		return err == nil && byr >= 1920 && byr <= 2002 && len(value) == 4
	case "iyr":
		iyr, err := strconv.Atoi(value)
		return err == nil && iyr >= 2010 && iyr <= 2020 && len(value) == 4
	case "eyr":
		eyr, err := strconv.Atoi(value)
		return err == nil && eyr >= 2020 && eyr <= 2030 && len(value) == 4
	case "hgt":
		if strings.HasSuffix(value, "cm") {
			hgt, err := strconv.Atoi(strings.TrimRight(value, "cm"))
			return err == nil && hgt >= 150 && hgt <= 193
		} else if strings.HasSuffix(value, "in") {
			hgt, err := strconv.Atoi(strings.TrimRight(value, "in"))
			return err == nil && hgt >= 59 && hgt <= 76
		} else {
			return false
		}
	case "hcl":
		matched, err := regexp.MatchString(`^#[0-9a-f]{6}$`, value)
		return err == nil && matched
	case "ecl":
		options := map[string]struct{}{
			"amb": {},
			"blu": {},
			"brn": {},
			"gry": {},
			"grn": {},
			"hzl": {},
			"oth": {},
		}
		_, ok := options[value]
		return ok
	case "pid":
		_, err := strconv.Atoi(value)
		return err == nil && len(value) == 9
	default:
		return false
	}
}