feat: day 2 and template

2024/1/1.go

@@ -49,6 +49,7 @@ func p2(data []string) int {
 	var totalSimilarity int
 
 	for i := 0; i < len(data); i++ {
+		// day2 - I could've used strings.Fields
 		splitData := strings.Split(data[i], "   ")
 		splitInt, err := sliceAtoi(splitData)
 		if err != nil {

2024/2/2.go

@@ -0,0 +1,91 @@
+package main
+
+import (
+	"fmt"
+	"math"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// each line is one report, one number in a report is a level
+func p1(data []string) int {
+	safeReports := 0
+    for _, line := range data {
+        levels := sliceAtoi(strings.Fields(line))
+        if isValidSequence(levels) {
+            safeReports++
+        }
+    }
+    return safeReports
+}
+
+func p2(data []string) int {
+    safeReports := 0
+    
+    for _, line := range data {
+        levels := sliceAtoi(strings.Fields(line))
+        
+        // check original sequence
+        if isValidSequence(levels) {
+            safeReports++
+            continue
+        }
+        
+        // try removing one level at a time
+        for i := range levels {
+            newLevels := make([]int, 0, len(levels)-1)
+            newLevels = append(newLevels, levels[:i]...)
+            newLevels = append(newLevels, levels[i+1:]...)
+            
+            if isValidSequence(newLevels) {
+                safeReports++
+                break
+            }
+        }
+    }
+    return safeReports
+}
+
+func main() {
+	data, err := os.ReadFile("input.txt")
+	if err != nil {
+		fmt.Println("File reading error", err)
+		return
+	}
+	lines := strings.Split(string(data), "\n")
+
+	fmt.Println("Part 1:", p1(lines))
+	fmt.Println("Part 2:", p2(lines))
+}
+
+// HELPER FUNCTIONS
+
+// day1, modified to ignore error https://stackoverflow.com/a/24973180
+func sliceAtoi(sa []string) []int {
+	si := make([]int, 0, len(sa))
+	for _, a := range sa {
+		i, _ := strconv.Atoi(a)
+		si = append(si, i)
+	}
+	return si
+}
+
+func isValidSequence(levels []int) bool {
+    if len(levels) < 2 {
+        return false
+    }
+    
+    isIncreasing := levels[1] > levels[0]
+    
+    for i := 1; i < len(levels); i++ {
+        diff := levels[i] - levels[i-1]
+        if math.Abs(float64(diff)) < 1 || math.Abs(float64(diff)) > 3 {
+            return false
+        }
+        if (isIncreasing && diff <= 0) || (!isIncreasing && diff >= 0) {
+            return false
+        }
+    }
+    return true
+}

2024/template.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+func p1(data []string) int {
+	
+}
+
+/* func p2(data []string) int {
+	
+} */
+
+func main() {
+	data, err := os.ReadFile("input.txt")
+	if err != nil {
+		fmt.Println("File reading error", err)
+		return
+	}
+	lines := strings.Split(string(data), "\n")
+
+	fmt.Println("Part 1:", p1(lines))
+	// fmt.Println("Part 2:", p2(lines))
+}