d2p2.go

package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"slices"
	"strconv"
	"strings"
)

func checkSafety(report_slice_int []int) bool {
	if slices.IsSorted(report_slice_int) || slices.IsSortedFunc(report_slice_int, func(a, b int) int {
		if a < b {
			return 1
		}
		if a > b {
			return -1
		}
		return 0
	}) {
		safe := true
		for i := 0; i < len(report_slice_int)-1; i++ {
			diff := math.Abs(float64(report_slice_int[i] - report_slice_int[i+1]))
			if diff == 0 || diff > 3 {
				safe = false
			}
		}

		if safe {
			return true
		}
	}
	return false
}

func main() {
	scan := bufio.NewScanner(os.Stdin)
	var safe_reports int

	for scan.Scan() {
		report := scan.Text()
		report_slice := strings.Split(report, " ")
		var report_slice_int []int

		for _, i := range report_slice {
			j, _ := strconv.Atoi(i)
			report_slice_int = append(report_slice_int, j)
		}

		if checkSafety(report_slice_int) {
			safe_reports++
		} else {
			for i := 0; i < len(report_slice_int); i++ {
				report_slice_int_mod := append(make([]int, 0, len(report_slice_int)), report_slice_int...)
				slices.Delete(report_slice_int_mod, i, i+1)
				if checkSafety(report_slice_int_mod[:len(report_slice_int)-1]) {
					safe_reports++
					break
				}
			}
		}

	}
	fmt.Println(safe_reports)
}