Do day one and two

three.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func check(e error) {
+	if e != nil {
+		panic(e)
+	}
+}
+
+func is_safe(levels []int) bool {
+	all_diffs_neg := true
+	all_diffs_pos := true
+
+	prev := levels[0]
+	for i, level := range levels {
+		if i == 0 {
+			prev = level
+			continue
+		}
+
+		diff := level - prev
+		if diff > 3 || diff < -3 || diff == 0 {
+			return false
+		}
+
+		all_diffs_pos = all_diffs_pos && diff > 0
+		all_diffs_neg = all_diffs_neg && diff < 0
+		prev = level
+	}
+
+	return all_diffs_neg || all_diffs_pos
+}
+
+func is_safe_with_dampener(levels []int) bool {
+	if is_safe(levels) {
+		return true
+	}
+
+	for i := range levels {
+		damped_levels := make([]int, 0, len(levels)-1)
+		for j, val := range levels {
+			if i == j {
+				continue
+			}
+
+			damped_levels = append(damped_levels, val)
+		}
+
+		if is_safe(damped_levels) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func main() {
+	f, err := os.Open("./two.txt")
+	defer f.Close()
+	check(err)
+
+	n_safe := 0
+	n_dampener_safe := 0
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+
+		line := scanner.Text()
+		fields := strings.Fields(line)
+
+		levels := make([]int, 0, 5)
+
+		for _, field := range fields {
+			level, err := strconv.Atoi(field)
+			check(err)
+			levels = append(levels, level)
+		}
+		if is_safe(levels) {
+			n_safe += 1
+		}
+		if is_safe_with_dampener(levels) {
+			n_dampener_safe += 1
+		}
+	}
+
+	fmt.Println(n_safe)
+	fmt.Println(n_dampener_safe)
+}

two.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func check(e error) {
+	if e != nil {
+		panic(e)
+	}
+}
+
+func is_safe(levels []int) bool {
+	all_diffs_neg := true
+	all_diffs_pos := true
+
+	prev := levels[0]
+	for i, level := range levels {
+		if i == 0 {
+			prev = level
+			continue
+		}
+
+		diff := level - prev
+		if diff > 3 || diff < -3 || diff == 0 {
+			return false
+		}
+
+		all_diffs_pos = all_diffs_pos && diff > 0
+		all_diffs_neg = all_diffs_neg && diff < 0
+		prev = level
+	}
+
+	return all_diffs_neg || all_diffs_pos
+}
+
+func is_safe_with_dampener(levels []int) bool {
+	if is_safe(levels) {
+		return true
+	}
+
+	for i := range levels {
+		damped_levels := make([]int, 0, len(levels)-1)
+		for j, val := range levels {
+			if i == j {
+				continue
+			}
+
+			damped_levels = append(damped_levels, val)
+		}
+
+		if is_safe(damped_levels) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func main() {
+	f, err := os.Open("./two.txt")
+	defer f.Close()
+	check(err)
+
+	n_safe := 0
+	n_dampener_safe := 0
+
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+
+		line := scanner.Text()
+		fields := strings.Fields(line)
+
+		levels := make([]int, 0, 5)
+
+		for _, field := range fields {
+			level, err := strconv.Atoi(field)
+			check(err)
+			levels = append(levels, level)
+		}
+		if is_safe(levels) {
+			n_safe += 1
+		}
+		if is_safe_with_dampener(levels) {
+			n_dampener_safe += 1
+		}
+	}
+
+	fmt.Println(n_safe)
+	fmt.Println(n_dampener_safe)
+}