add: exercises and quiz for appending and slicing

16-slices/exercises/14-slicing-by-args/solution/main.go

@@ -0,0 +1,42 @@
+// For more tutorials: https://blog.learngoprogramming.com
+//
+// Copyright © 2018 Inanc Gumus
+// Learn Go Programming Course
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+//
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+)
+
+func main() {
+	ships := []string{"Normandy", "Verrikan", "Nexus", "Warsaw"}
+
+	fmt.Printf("%q\n\n", ships)
+
+	from, to := 0, len(ships)
+
+	switch poss := os.Args[1:]; len(poss) {
+	default:
+		fallthrough
+	case 0:
+		fmt.Println("Provide only the [starting] and [stopping] positions")
+		return
+	case 2:
+		to, _ = strconv.Atoi(poss[1])
+		fallthrough
+	case 1:
+		from, _ = strconv.Atoi(poss[0])
+	}
+
+	if l := len(ships); from < 0 || from > l || to > l || from > to {
+		fmt.Println("Wrong positions")
+		return
+	}
+
+	fmt.Println(ships[from:to])
+}