add: array led clock exercises

etc/stratch/main.go

@@ -1,129 +1,4 @@
 package main
 
-import (
-	"fmt"
-	"time"
-
-	"github.com/inancgumus/screen"
-)
-
 func main() {
-	type placeholder [5]string
-
-	zero := placeholder{"███", "█ █", "█ █", "█ █", "███"}
-	one := placeholder{"██ ",
-		" █ ",
-		" █ ",
-		" █ ",
-		"███",
-	}
-
-	two := placeholder{
-		"███",
-		"  █",
-		"███",
-		"█  ",
-		"███",
-	}
-
-	three := placeholder{
-		"███",
-		"  █",
-		"███",
-		"  █",
-		"███",
-	}
-
-	four := placeholder{
-		"█ █",
-		"█ █",
-		"███",
-		"  █",
-		"  █",
-	}
-
-	five := placeholder{
-		"███",
-		"█  ",
-		"███",
-		"  █",
-		"███",
-	}
-
-	six := placeholder{
-		"███",
-		"█  ",
-		"███",
-		"█ █",
-		"███",
-	}
-
-	seven := placeholder{
-		"███",
-		"  █",
-		"  █",
-		"  █",
-		"  █",
-	}
-
-	eight := placeholder{
-		"███",
-		"█ █",
-		"███",
-		"█ █",
-		"███",
-	}
-
-	nine := placeholder{
-		"███",
-		"█ █",
-		"███",
-		"  █",
-		"███",
-	}
-
-	colon := placeholder{
-		"   ",
-		" ░ ",
-		"   ",
-		" ░ ",
-		"   ",
-	}
-
-	digits := [...]placeholder{
-		zero, one, two, three, four, five, six, seven, eight, nine,
-	}
-
-	screen.Clear()
-
-	for {
-		screen.MoveTopLeft()
-
-		now := time.Now()
-		hour, min, sec := now.Hour(), now.Minute(), now.Second()
-
-		// [8][5]string -> [8]placeholder
-		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 {
-				next := clock[index][line]
-				if digit == colon && sec%2 == 0 {
-					next = "   "
-				}
-
-				fmt.Print(next, "  ")
-			}
-			fmt.Println()
-		}
-		fmt.Println()
-
-		time.Sleep(time.Second)
-	}
 }