Added the first days

2021/02/first.b98

@@ -0,0 +1,5 @@
+v                      pos in 0,0, depth in 1,0
+>00p10p>#;~:'f-#v_$&00g+00p     v@,a.*g01g00;
+                >'d-#v_$&10g+10pv
+                     >&10g\-10p v
+       ^         ;,a.g01.g00; ~ <  # we do not forget to strip the \n from the input

2021/02/first.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	f, err := os.Open("input")
+	if err != nil {
+		log.Fatalf("%+v", err)
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	scanner.Split(bufio.ScanLines)
+
+	pos := 0
+	depth := 0
+	for scanner.Scan() {
+		elts := strings.Split(scanner.Text(), " ")
+		i, err := strconv.Atoi(elts[1])
+		if err != nil {
+			log.Fatalf("%+v", err)
+		}
+		switch elts[0] {
+		case "forward":
+			pos += i
+		case "down":
+			depth += i
+		case "up":
+			depth -= i
+		default:
+			panic(elts[0])
+		}
+	}
+	fmt.Println(pos * depth)
+}

2021/02/second.b98

@@ -0,0 +1,5 @@
+v                      pos in 0,0, depth in 1,0, aim in 2,0
+>00p10p20p>#;~:'f-#v_$&:00g+00p     v@,a.*g01g00;
+                   >'d-#v_$&20g+20pv>20g*10g+10pv
+                        >&20g\-20p v            <
+          ^         ;,a.g01.g00; ~ << # we do not forget to strip the \n from the input

2021/02/second.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	f, err := os.Open("input")
+	if err != nil {
+		log.Fatalf("%+v", err)
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	scanner.Split(bufio.ScanLines)
+
+	aim := 0
+	pos := 0
+	depth := 0
+	for scanner.Scan() {
+		elts := strings.Split(scanner.Text(), " ")
+		i, err := strconv.Atoi(elts[1])
+		if err != nil {
+			log.Fatalf("%+v", err)
+		}
+		switch elts[0] {
+		case "forward":
+			pos += i
+			depth += i * aim
+		case "down":
+			aim += i
+		case "up":
+			aim -= i
+		default:
+			panic(elts[0])
+		}
+	}
+	fmt.Println(pos * depth)
+}