add: arrays

14-arrays/exercises/02-get-set-arrays/main.go

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+package main
+
+// ---------------------------------------------------------
+// EXERCISE: Get and Set Array Elements
+//
+//  1. Use the 01-declare-empty exercise
+//  2. Remove everything but the array declarations
+//
+//  3. Assign your best friends' names to the names array
+//
+//  4. Assign distances to the closest cities to you to the distance array
+//
+//  5. Assign arbitrary bytes to the data array
+//
+//  6. Assign a value to the ratios array
+//
+//  7. Assign true/false values to the alives arrays
+//
+//  8. Try to assign to the zero array and observe the error
+//
+//  9. Now use ordinary loop statements for each array and print them
+//      (do not use for range)
+//
+//  10. Now use for range loop statements for each array and print them
+//
+//  11. Try assigning different types of values to the arrays, break things,
+//     and observe the errors
+//
+//  12. Remove some of the array assignments and observe the loop outputs
+//      (zero values)
+//
+//
+// EXPECTED OUTPUT
+//
+//  Note: The output can change depending on the values that you've assigned to them, of course.
+//        You're free to assign any values.
+//
+//   names
+//   ====================
+//   names[0]: "Einstein"
+//   names[1]: "Tesla"
+//   names[2]: "Shepard"
+//
+//   distances
+//   ====================
+//   distances[0]: 50
+//   distances[1]: 40
+//   distances[2]: 75
+//   distances[3]: 30
+//   distances[4]: 125
+//
+//   data
+//   ====================
+//   data[0]: 72
+//   data[1]: 69
+//   data[2]: 76
+//   data[3]: 76
+//   data[4]: 79
+//
+//   ratios
+//   ====================
+//   ratios[0]: 3.14
+//
+//   alives
+//   ====================
+//   alives[0]: true
+//   alives[1]: false
+//   alives[2]: true
+//   alives[3]: false
+//
+//   zero
+//   ====================
+
+//
+//   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//   FOR RANGES
+//   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+//   names
+//   ====================
+//   names[0]: "Einstein"
+//   names[1]: "Tesla"
+//   names[2]: "Shepard"
+//
+//   distances
+//   ====================
+//   distances[0]: 50
+//   distances[1]: 40
+//   distances[2]: 75
+//   distances[3]: 30
+//   distances[4]: 125
+//
+//   data
+//   ====================
+//   data[0]: 72
+//   data[1]: 69
+//   data[2]: 76
+//   data[3]: 76
+//   data[4]: 79
+//
+//   ratios
+//   ====================
+//   ratios[0]: 3.14
+//
+//   alives
+//   ====================
+//   alives[0]: true
+//   alives[1]: false
+//   alives[2]: true
+//   alives[3]: false
+//
+//   zero
+//   ====================
+//
+// ---------------------------------------------------------
+
+func main() {
+}

14-arrays/exercises/02-get-set-arrays/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"
+	"strings"
+)
+
+func main() {
+	var (
+		names     [3]string  // The names of your best three friends
+		distances [5]int     // The distances to five different locations
+		data      [5]byte    // A data buffer with five bytes of capacity
+		ratios    [1]float64 // Currency exchange ratios only for a single currency
+		alives    [4]bool    // Up/Down status of four different web servers
+		zero      [0]byte    // A byte array that doesn't occupy memory space
+	)
+
+	names[0] = "Einstein"
+	names[1] = "Tesla"
+	names[2] = "Shepard"
+
+	distances[0] = 50
+	distances[1] = 40
+	distances[2] = 75
+	distances[3] = 30
+	distances[4] = 125
+
+	data[0] = 'H'
+	data[1] = 'E'
+	data[2] = 'L'
+	data[3] = 'L'
+	data[4] = 'O'
+
+	ratios[0] = 3.14145
+
+	alives[0] = true
+	alives[1] = false
+	alives[2] = true
+	alives[3] = false
+
+	// zero[0] = "BOMB!"
+	_ = zero
+
+	// =========================================================================
+
+	separator := "\n" + strings.Repeat("=", 20) + "\n"
+
+	fmt.Print("names", separator)
+	for i := 0; i < len(names); i++ {
+		fmt.Printf("names[%d]: %q\n", i, names[i])
+	}
+
+	fmt.Print("\ndistances", separator)
+	for i := 0; i < len(distances); i++ {
+		fmt.Printf("distances[%d]: %d\n", i, distances[i])
+	}
+
+	fmt.Print("\ndata", separator)
+	for i := 0; i < len(data); i++ {
+		// try the %c verb
+		fmt.Printf("data[%d]: %d\n", i, data[i])
+	}
+
+	fmt.Print("\nratios", separator)
+	for i := 0; i < len(ratios); i++ {
+		fmt.Printf("ratios[%d]: %.2f\n", i, ratios[i])
+	}
+
+	fmt.Print("\nalives", separator)
+	for i := 0; i < len(alives); i++ {
+		fmt.Printf("alives[%d]: %t\n", i, alives[i])
+	}
+
+	// no loop for zero elements
+	fmt.Print("\nzero", separator)
+	for i := 0; i < len(zero); i++ {
+		fmt.Printf("zero[%d]: %d\n", i, zero[i])
+	}
+
+	// =========================================================================
+
+	// you know how this works :) don't be freaked out!
+	fmt.Printf(`
+
+%s
+FOR RANGES
+%[1]s
+
+`, strings.Repeat("~", 30))
+
+	fmt.Print("names", separator)
+	for i, v := range names {
+		fmt.Printf("names[%d]: %q\n", i, v)
+	}
+
+	fmt.Print("\ndistances", separator)
+	for i, v := range distances {
+		fmt.Printf("distances[%d]: %d\n", i, v)
+	}
+
+	fmt.Print("\ndata", separator)
+	for i, v := range data {
+		// try the %c verb
+		fmt.Printf("data[%d]: %d\n", i, v)
+	}
+
+	fmt.Print("\nratios", separator)
+	for i, v := range ratios {
+		fmt.Printf("ratios[%d]: %.2f\n", i, v)
+	}
+
+	fmt.Print("\nalives", separator)
+	for i, v := range alives {
+		fmt.Printf("alives[%d]: %t\n", i, v)
+	}
+
+	// no loop for zero elements
+	fmt.Print("\nzero", separator)
+	for i, v := range zero {
+		fmt.Printf("zero[%d]: %d\n", i, v)
+	}
+}