adventofcode/2017/day04/day04.go

package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

func main() {
	inp := StdinToStrings()
	part1(inp)
	part2(inp)
}

func findValid(inp []string, cmp func(string, string) bool) {
	cnt := 0
	for _, v := range inp {
		wrds := strings.Split(v, " ")
		isGood := true
		for i := range wrds {
			for j := i + 1; j < len(wrds); j++ {
				if cmp(wrds[i], wrds[j]) {
					isGood = false
				}
				if !isGood {
					break
				}
			}
			if !isGood {
				break
			}
		}
		if isGood {
			cnt++
		}
	}
	fmt.Println("Valid Passphrases:", cnt)
}

func part1(inp []string) {
	fmt.Println("== Part 1 ==")
	cmp := func(wrd1, wrd2 string) bool {
		return wrd1 == wrd2
	}
	findValid(inp, cmp)
}

func part2(inp []string) {
	fmt.Println("== Part 2 ==")
	cmp := func(wrd1, wrd2 string) bool {
		return isAnagram(wrd1, wrd2)
	}
	findValid(inp, cmp)
}

func isAnagram(wrd1, wrd2 string) bool {
	charMap := make(map[byte]int)
	for i := range wrd1 {
		charMap[wrd1[i]]++
	}
	for i := range wrd2 {
		charMap[wrd2[i]]--
	}
	for _, v := range charMap {
		if v != 0 {
			return false
		}
	}
	return true
}

func StdinToStrings() []string {
	var input []string
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		input = append(input, scanner.Text())
	}
	return input
}