advent of code day1 (go)

main.go

package main

import (
	"bufio"
	"log"
	"os"
	"sort"
	"strconv"
	"strings"
)

func main() {
	inputs, err := os.Open("inputs")
	if err != nil {
		log.Println(err)
		return
	}
	defer inputs.Close()
	var lst1, lst2 []int
	scan := bufio.NewScanner(inputs)
	for scan.Scan() {
		line := scan.Text()
		parts := strings.Fields(line)
		if len(parts) < 2 {
			log.Println("mismatched input")
			return
		}
		for i, v := range parts {
			vv, _ := strconv.Atoi(v)
			if i == 0 {
				lst1 = append(lst1, vv)
			} else {
				lst2 = append(lst2, vv)
			}
		}
	}
	sort.Ints(lst1)
	sort.Ints(lst2)
	if len(lst1) != len(lst2) {
		log.Println("mismatched slices")
		return
	}
	var total int
	for i := 0; i < len(lst1); i++ {
		a, b := lst1[i], lst2[i]
		if a > b {
			total += a - b
		} else {
			total += b - a
		}
		// log.Println(total, a, b)
	}
	log.Println(total)
}

part2

	var total int
	for i := 0; i < len(lst1); i++ {
		var count int
		for j := 0; j < len(lst2); j++ {
			a, b := lst1[i], lst2[j]
			if a == b {
				count++
			}
		}
		total += lst1[i] * count
	}
	log.Println(total)