89 lines
1.3 KiB
Go
89 lines
1.3 KiB
Go
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package main
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import (
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"bufio"
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_ "embed"
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"fmt"
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"strings"
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aoc "go.sour.is/advent-of-code"
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)
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// var log = aoc.Log
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func main() { aoc.MustResult(aoc.Runner(run)) }
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type result struct {
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valuePT1 int
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valuePT2 int
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}
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func (r result) String() string { return fmt.Sprintf("%#v", r) }
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func run(scan *bufio.Scanner) (*result, error) {
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sum := 0
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sum2 := 0
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for scan.Scan() {
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txt := scan.Text()
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row := aoc.ReadStringToInts(strings.Fields(txt))
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good, bad := testSafety(row)
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if good {
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sum++
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sum2++
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continue
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}
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for i := max(0, bad-1); i < min(bad+2, len(row)); i++ {
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arr := cut(i, row)
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good, _ := testSafety(arr)
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if good {
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sum2++
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break
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}
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}
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}
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return &result{valuePT1: sum, valuePT2: sum2}, nil
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}
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func testSafety(row []int) (bool, int) {
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good := true
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bad := -1
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increasing := false
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decreasing := false
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for i, v := range row[1:] {
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if v > row[i] {
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increasing = true
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}
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if v < row[i] {
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decreasing = true
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}
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if difference := aoc.ABS(v - row[i]); difference < 1 || difference > 3 {
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good = false
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bad = i
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break
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}
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if increasing && decreasing {
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good = false
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bad = i
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break
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}
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}
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return good, bad
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}
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func cut(i int, values []int) []int {
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arr := make([]int, 0, len(values))
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arr = append(arr, values[:i]...)
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arr = append(arr, values[i+1:]...)
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return arr
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}
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