Advent of Code 2021 Day 1

1a.go

package main

import (
	_ "embed"
	"fmt"
	"strconv"
	"strings"
)

//go:embed input.txt
var input string

func main() {
	last := -1
	bigger := 0

	lines := strings.Split(input, "\n")
	for _, line := range lines {
		num, err := strconv.Atoi(line)
		if err != nil {
			panic(err)
		}

		if last != -1 && num > last {
			bigger++
		}
		last = num
	}
	fmt.Println(bigger)
}

1b.go

package main

import (
	_ "embed"
	"fmt"
	"strconv"
	"strings"
)

//go:embed input.txt
var input string

func main() {
	lines := strings.Split(input, "\n")
	vals := make([]int, len(lines))
	// parse
	for i, line := range lines {
		num, err := strconv.Atoi(line)
		if err != nil {
			panic(err)
		}
		vals[i] = num
	}

	// calculate windows
	sums := make([]int, 0)
	for len(vals) >= 3 {
		sums = append(sums, vals[0]+vals[1]+vals[2])
		vals = vals[1:]
	}

	// calculate diffs
	out := 0
	for i, val := range sums[1:] {
		if val > sums[i] {
			out++
		}
	}
	fmt.Println(out)
}