restructure: arrays and slices

15-project-retro-led-clock/exercises/02-alarm/main.go

@@ -0,0 +1,87 @@
+// 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/
+//
+
+// ---------------------------------------------------------
+// EXERCISE: Set an Alarm
+//
+//  Goal is printing " ALARM! " every 10 seconds.
+//
+// EXPECTED OUTPUT
+//
+//     ██   ███       ███  ██        ███  ███
+//      █     █   ░     █   █    ░     █  █ █
+//      █   ███       ███   █        ███  ███
+//      █   █     ░     █   █    ░     █    █
+//     ███  ███       ███  ███       ███  ███
+//
+//          ███  █    ███  ██   █ █   █
+//          █ █  █    █ █  █ █  ███   █
+//          ███  █    ███  ██   █ █   █
+//          █ █  █    █ █  █ █  █ █
+//          █ █  ███  █ █  █ █  █ █   █
+//
+//     ██   ███       ███  ██        █ █  ██
+//      █     █   ░     █   █    ░   █ █   █
+//      █   ███       ███   █        ███   █
+//      █   █     ░     █   █    ░     █   █
+//     ███  ███       ███  ███         █  ███
+//
+// HINTS
+//
+//  <<< BEWARE THE SPOILER! >>>
+//
+//  I recommend you to first solve the exercise yourself before reading the
+//  following hint.
+//
+//
+//  + You can create a new array named alarm with the same length of the
+//    clocks array, so you can copy the alarm array to the clocks array
+//    every 10 seconds.
+//
+// ---------------------------------------------------------
+
+package main
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/inancgumus/screen"
+)
+
+func main() {
+	screen.Clear()
+
+	for {
+		screen.MoveTopLeft()
+
+		now := time.Now()
+		hour, min, sec := now.Hour(), now.Minute(), now.Second()
+
+		clock := [...]placeholder{
+			digits[hour/10], digits[hour%10],
+			colon,
+			digits[min/10], digits[min%10],
+			colon,
+			digits[sec/10], digits[sec%10],
+		}
+
+		for line := range clock[0] {
+			for index, digit := range clock {
+				// colon blink
+				next := clock[index][line]
+				if digit == colon && sec%2 == 0 {
+					next = "   "
+				}
+				fmt.Print(next, "  ")
+			}
+			fmt.Println()
+		}
+
+		time.Sleep(time.Second)
+	}
+}