add: array exercises

14-arrays/exercises/12-sorter/main.go

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+package main
+
+// ---------------------------------------------------------
+// EXERCISE: Number Sorter
+//
+//  Your goal is to sort the given numbers from the command-line.
+//
+//  1. Get the numbers from the command-line.
+//
+//  2. Create an array and assign the given numbers to that array.
+//
+//  3. Sort the given numbers and print them.
+//
+// RESTRICTION
+//   + Maximum 5 numbers can be provided
+//   + If one of the arguments are not a valid number, skip it
+//
+// HINTS
+//  + You can use the bubble-sort algorithm to sort the numbers.
+//    Please watch this: https://youtu.be/nmhjrI-aW5o?t=7
+//
+//  + When swapping for elements, do not check for the last element.
+//    Or, you will receive this error:
+//    "panic: runtime error: index out of range"
+//
+// EXPECTED OUTPUT
+//   go run main.go
+//     Please give me up to 5 numbers.
+//
+//   go run main.go 6 5 4 3 2 1
+//     Sorry. Go arrays are fixed. So, for now, I'm only supporting sorting 5 numbers...
+//
+//   go run main.go 5 4 3 2 1
+//     [1 2 3 4 5]
+//
+//   go run main.go 5 4 a c 1
+//     [0 0 1 4 5]
+// ---------------------------------------------------------
+
+func main() {
+}

14-arrays/exercises/12-sorter/solution/main.go

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+// 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() {
+	args := os.Args[1:]
+
+	switch l := len(args); {
+	case l == 0:
+		fmt.Println("Please give me up to 5 numbers.")
+		return
+	case l > 5:
+		fmt.Println("Sorry. Go arrays are fixed.",
+			"So, for now, I'm only supporting sorting 5 numbers...")
+		return
+	}
+
+	var nums [5]float64
+
+	// fill the array with the numbers
+	for i, v := range args {
+		n, err := strconv.ParseFloat(v, 64)
+		if err != nil {
+			// skip if it's not a valid number
+			continue
+		}
+
+		nums[i] = n
+	}
+
+	/*
+		check whether it's the last element or not:
+		  i < len(nums)-1
+
+		check whether the next number is greater than the current one, if so, swap it:
+		  v > nums[i+1]
+	*/
+	for range nums {
+		for i, v := range nums {
+			if i < len(nums)-1 && v > nums[i+1] {
+				nums[i], nums[i+1] = nums[i+1], nums[i]
+			}
+		}
+	}
+
+	fmt.Println(nums)
+}