Golang solutions

answers/Go/@codehakase/01-name-concatenation.go

@@ -0,0 +1,22 @@
+package main
+
+import "fmt"
+
+func main() {
+	var (
+		firstname string
+		lastname  string
+		age       int
+	)
+	fmt.Print("Enter first name: ")
+	fmt.Scanf("%s\n", &firstname)
+
+	fmt.Print("Enter last name: ")
+	fmt.Scanf("%s\n", &lastname)
+
+	fmt.Print("Enter your age: ")
+	fmt.Scanf("%d\n", &age)
+	fmt.Print("\n")
+
+	fmt.Printf("Welcome, %s %s (%d)\n", firstname, lastname, age)
+}

answers/Go/@codehakase/02-lottery.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"math/rand"
+	"os"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().UnixNano())
+	var a, b, c int
+	for {
+		reader := bufio.NewReader(os.Stdin)
+		fmt.Print("Press Enter key to continue...")
+		_, _ = reader.ReadString('\n')
+		a = rand.Intn(10)
+		b = rand.Intn(10)
+		c = rand.Intn(10)
+		fmt.Printf("%d %d %d\n", a, b, c)
+		if a == 7 || b == 7 || c == 7 {
+			fmt.Println("Congratulations!!\n")
+		} else {
+			fmt.Println("Try again! Better luck next time.\n")
+		}
+	}
+}

answers/Go/@codehakase/03-word-in-reverse.go

@@ -0,0 +1,16 @@
+package main
+
+import "fmt"
+
+func main() {
+	var word string
+	for {
+		fmt.Print("Enter a word: ")
+		fmt.Scanf("%s\n", &word)
+
+		for i := len(word) - 1; i >= 0; i-- {
+			fmt.Printf("%c", word[i])
+		}
+		fmt.Println()
+	}
+}

answers/Go/@codehakase/04-type-in-reverse.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"reflect"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().UnixNano())
+	words := []string{"Discombobulated", "Paradise", "California", "Machinery"}
+	for {
+		var userInput string
+		randWord := words[rand.Intn(len(words))]
+		fmt.Printf("Type the word '%s' in reverse: ", randWord)
+		fmt.Scanf("%s\n", &userInput)
+		if reflect.DeepEqual(userInput, reverseStr(randWord)) {
+			fmt.Println("\u2705")
+		} else {
+			fmt.Println("\u274C")
+		}
+	}
+}
+
+func reverseStr(s string) string {
+	r := []rune(s)
+	for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 {
+		r[i], r[j] = r[j], r[i]
+	}
+	return string(r)
+}

answers/Go/@codehakase/05-temperature-unit-conversion.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+)
+
+// ErrInvalidUnit is returned when the unit from Stdin
+// is not one of the valid units.
+var ErrInvalidUnit = errors.New("invalid unit selected")
+
+// Unit represents a temperature unit
+type Unit int
+
+const (
+	// CelsiusToFahrenheit represets a celsius to fahrenheit conversion unit
+	CelsiusToFahrenheit Unit = 1
+	// FahrenheitToCelsius represets a farenheit to celsius conversion unit
+	FahrenheitToCelsius Unit = 2
+	// CelsiusToKelvin represets a celsius to kelvin conversion unit
+	CelsiusToKelvin Unit = 3
+	// KelvinToCelsius represets a kelvin to celsius conversion unit
+	KelvinToCelsius Unit = 4
+	// FahrenheitToKelvin represets a farenheit to kelvin conversion unit
+	FahrenheitToKelvin Unit = 5
+	// KelvinToFahrenheit represets a kelvin to fahrenheit conversion unit
+	KelvinToFahrenheit Unit = 6
+)
+
+func main() {
+	var (
+		optionUnit Unit
+		input      float64
+		conv       float64
+	)
+
+	for {
+		fmt.Print(notice())
+		fmt.Scanf("%d\n", &optionUnit)
+		switch optionUnit {
+		case CelsiusToFahrenheit:
+			fmt.Print("Enter a celsius value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input * (9.0 / 5.0)) + 32.0
+			fmt.Printf("Fahrenheit value is %.3f ⁰F\n", conv)
+		case FahrenheitToCelsius:
+			fmt.Print("Enter a fahrenheit value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input - 32) * (5.0 / 9.0)
+			fmt.Printf("Celsius value is %.3f ⁰F\n", conv)
+		case CelsiusToKelvin:
+			fmt.Print("Enter a celsius value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input + 273.15)
+			fmt.Printf("Kelvin value is %.3fK\n", conv)
+		case KelvinToCelsius:
+			fmt.Print("Enter kelvin value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input - 273.15)
+			fmt.Printf("Celsius value is %.3f ⁰C\n", conv)
+		case FahrenheitToKelvin:
+			fmt.Print("Enter a fahrenheit value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input-32)*(5.0/9.0) + 273.15
+			fmt.Printf("Kelvin value is %.3fK\n", conv)
+		case KelvinToFahrenheit:
+			fmt.Print("Enter kelvin value: ")
+			fmt.Scanf("%f\n", &input)
+			conv = (input-273.15)*(9.0/5.0) + 32
+			fmt.Printf("Fahrenheit value is %.3f ⁰F\n", conv)
+		default:
+			fmt.Println(ErrInvalidUnit)
+		}
+	}
+}
+
+func notice() string {
+	return `
+1. Celsius to Fahrenheit
+2. Fahrenheit to Celsius
+3. Celsius to Kelvin
+4. Kelvin to Celsius
+5. Fahrenheit to Kelvin
+6. Kelvin to Fahrenheit
+
+Enter an option: `
+}

answers/Go/@codehakase/06-multiplicaiton-table.go

@@ -0,0 +1,12 @@
+package main
+
+import "fmt"
+
+func main() {
+	for i := 1; i <= 12; i++ {
+		for j := 2; j <= 12; j++ {
+			fmt.Print(fmt.Sprintf("%v\t", i*j))
+		}
+		fmt.Println()
+	}
+}

answers/Go/@codehakase/07-read-line-by-line.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"time"
+)
+
+func main() {
+	file, err := os.OpenFile("./data/07-read-line-by-line.txt", os.O_RDONLY, os.ModePerm)
+	if err != nil {
+		log.Fatalf("failed to open file: %v", err)
+		os.Exit(1)
+	}
+	defer file.Close()
+	scanSimple(file)
+	//scanLinesToFile(file)
+	//delayedScan(file)
+}
+
+func scanSimple(file *os.File) {
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		fmt.Println(scanner.Text()) // read line
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatalf("failed to scan lines: %v", err)
+		os.Exit(1)
+	}
+}
+
+func delayedScan(file *os.File) {
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		fmt.Println(scanner.Text()) // read line
+		time.Sleep(time.Second * 1)
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatalf("failed to scan lines: %v", err)
+		os.Exit(1)
+	}
+}
+
+func scanLinesToFile(file *os.File) {
+	scanner := bufio.NewScanner(file)
+	newFile, err := os.Create("./read-line-to-file.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer newFile.Close()
+	for scanner.Scan() {
+		_, err := io.WriteString(newFile, fmt.Sprintf("%s\n", scanner.Text()))
+		if err != nil {
+			log.Fatal(err)
+		}
+		err = newFile.Sync()
+	}
+	if err := scanner.Err(); err != nil {
+		log.Fatalf("failed to scan lines: %v", err)
+		os.Exit(1)
+	}
+}

answers/Go/@codehakase/08-combine-two-files.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"strings"
+)
+
+func main() {
+	firstFile, err := ioutil.ReadFile("./data/08-combine-two-files-1.txt")
+	if err != nil {
+		log.Fatalf("failed to open file1: %v", err)
+	}
+	secondFile, err := ioutil.ReadFile("./data/08-combine-two-files-2.txt")
+	if err != nil {
+		log.Fatalf("failed to open file2: %v", err)
+	}
+	file1Words := strings.Split(string(firstFile), "\n")
+	file2Words := strings.Split(string(secondFile), "\n")
+	words := []string{}
+	for i := 0; i < len(file1Words); i++ {
+		word := fmt.Sprintf("%s %s\n", file1Words[i], file2Words[i])
+		words = append(words, word)
+	}
+	fmt.Println(strings.Join(words, ""))
+}

answers/Go/@codehakase/09-rgb-color-generator.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"math/rand"
+	"os"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().UnixNano())
+	for {
+		reader := bufio.NewReader(os.Stdin)
+		fmt.Print("Press enter to continue...")
+		reader.ReadString('\n')
+		fmt.Printf("%s\n", genRGBValues())
+	}
+}
+
+func genRGBValues() string {
+	var r, g, b int
+	r = rand.Intn(255)
+	g = rand.Intn(255)
+	b = rand.Intn(255)
+	return fmt.Sprintf("rgb(%d, %d, %d)", r, g, b)
+}

answers/Go/@codehakase/10-hex-color-generator.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"strconv"
+	"time"
+)
+
+func main() {
+	rand.Seed(time.Now().UnixNano())
+
+	fmt.Printf("#%s%s%s\n",
+		strconv.FormatInt(int64(rand.Intn(256)), 16),
+		strconv.FormatInt(int64(rand.Intn(256)), 16),
+		strconv.FormatInt(int64(rand.Intn(256)), 16))
+}

answers/Go/@codehakase/11-extract-file-ext.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+)
+
+func main() {
+	paths := []string{
+		"/Users/mykeels/Documents/file.txt",
+		"/Users/mykeels/Documents/file.csv",
+		"/Users/mykeels/Music/a-whole-new-world.mp3",
+		"/Users/mykeels/Movies/a-day-to-remember.mp4",
+	}
+	for _, path := range paths {
+		parts := strings.Split(path, ".")
+		fmt.Println(parts[len(parts)-1])
+	}
+}

answers/Go/@codehakase/12-salary-classifier.go

@@ -0,0 +1,22 @@
+package main
+
+import "fmt"
+
+func main() {
+	var salary int
+	for {
+		fmt.Print("Enter salary amount: ")
+		fmt.Scanf("%d\n", &salary)
+		if salary < 1 {
+			fmt.Println("Invalid salary amount")
+		}
+		if salary < 50000 {
+			fmt.Println("Basic Earner")
+		} else if salary <= 200000 {
+			fmt.Println("Mid Earner")
+		}
+		if salary > 200000 {
+			fmt.Println("High Earner")
+		}
+	}
+}