attempt 1 at day 2 part 1

02/input-ex

@@ -0,0 +1,6 @@
+7 6 4 2 1
+1 2 7 8 9
+9 7 6 2 1
+1 3 2 4 5
+8 6 4 4 1
+1 3 6 7 9

02/main.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+type Report struct {
+	number    int
+	levels    []int
+	valid     bool
+	direction string
+}
+
+// Reports stored one per line with levels in each column.
+// In safe reports, the levels are either all increasing or all decreasing AND
+// Any two adjacent levels differ by at least one and at most three.
+func main() {
+	input, err := os.ReadFile("input")
+	if err != nil {
+		fmt.Println(err)
+	}
+	var reports []Report
+
+	lines := strings.Split(string(input), "\n")
+	for idx, val := range lines[0 : len(lines)-1] {
+		reportFields := strings.Fields(val)
+		report := Report{
+			number:    idx,
+			valid:     true,
+			direction: "ASC",
+		}
+		for _, field := range reportFields {
+			reportVal, err := strconv.Atoi(field)
+			if err != nil {
+				break
+			}
+
+			report.valid = IsValidReport(&report, reportVal)
+
+			report.levels = append(report.levels, reportVal)
+		}
+		reports = append(reports, report)
+	}
+
+	var valid int
+	for _, report := range reports {
+		fmt.Printf("%v\n", report)
+		if report.valid {
+			valid++
+		}
+	}
+
+	fmt.Printf("Total: %v Valid %v\n", len(reports), valid)
+}
+
+func IsValidReport(report *Report, reportVal int) bool {
+	if !report.valid {
+		return false
+	}
+	valid := true
+	if len(report.levels) >= 1 {
+		fmt.Printf("===reportVal===: %v\n", reportVal)
+		fmt.Printf("levels: %v\n", report.levels)
+		last := report.levels[len(report.levels)-1]
+		// if len(report.levels) == 1 {
+		// 	last = 0
+		// }
+		fmt.Printf("last: %v\n", last)
+
+		// Determine direction
+		fmt.Printf("direction: %v\n", report.direction)
+		if len(report.levels) == 1 {
+			report.direction = DetermineDirection(report.levels[0], reportVal)
+		}
+		fmt.Printf("direction: %v\n", report.direction)
+
+		fmt.Printf("valid: %v\n", valid)
+		switch report.direction {
+		case "ASC":
+			if last > reportVal {
+				valid = false
+			}
+		case "DESC":
+			if last < reportVal {
+				valid = false
+			}
+		}
+		fmt.Printf("valid: %v\n", valid)
+		// fmt.Printf("abs(%v-%v)=%v\n", reportVal, last, Abs(reportVal-last))
+		// Check if our deltas are OK
+		delta := Abs(reportVal - last)
+
+		fmt.Printf("delta: %v\n", delta)
+		// fmt.Printf("abs(%v-%v)=%v\n", reportVal, last, Abs(reportVal-last))
+		if delta < 1 || delta > 3 {
+			valid = false
+		}
+		fmt.Printf("valid: %v\n", valid)
+		fmt.Printf("\n\n")
+	}
+	return valid
+}
+
+func DetermineDirection(one, two int) string {
+	diff := one - two
+	if diff < 0 {
+		return "ASC"
+	}
+	return "DESC"
+}
+
+func Abs(input int) int {
+	if input < 0 {
+		return -input
+	}
+	return input
+}