Multiplication tables
You are encouraged to solve this task according to the task description, using any language you may know.
Produce a formatted 12×12 multiplication table of the kind memorised by rote when in primary school.
Only print the top half triangle of products.
ALGOL 68
<lang Algol68>main:(
INT max = 12; STRING empty cell = " "; FORMAT fmt = $zz-d$;
print(" x");
FOR col TO max DO printf((fmt, col)) OD;
print (new line);
FOR row TO max DO printf((fmt,row)); FOR col TO row-1 DO print(empty cell) OD; [row:max]INT product; FOR col FROM row TO max DO product[col]:=row*col OD; printf((fmt, product, $l$)) OD
)</lang> Output:
x 1 2 3 4 5 6 7 8 9 10 11 12 1 1 2 3 4 5 6 7 8 9 10 11 12 2 4 6 8 10 12 14 16 18 20 22 24 3 9 12 15 18 21 24 27 30 33 36 4 16 20 24 28 32 36 40 44 48 5 25 30 35 40 45 50 55 60 6 36 42 48 54 60 66 72 7 49 56 63 70 77 84 8 64 72 80 88 96 9 81 90 99 108 10 100 110 120 11 121 132 12 144
Haskell
<lang haskell>import Text.Printf
main = do
putStrLn $ " x" ++ concatMap fmt [1..12]
mapM_ putStrLn $ zipWith f [1..12] $ iterate (" " ++) ""
where f n s = fmt n ++ s ++ concatMap (fmt . (*n)) [n..12]
fmt n = printf "%4d" (n :: Int)</lang>
Python
<lang python>>>> for row in range(13): print(" ".join("%3s" % ("x" if row==col==0 else row if row and col==0 else col if row==0 else "" if row>col else row*col) for col in range(13)))
x 1 2 3 4 5 6 7 8 9 10 11 12 1 1 2 3 4 5 6 7 8 9 10 11 12 2 4 6 8 10 12 14 16 18 20 22 24 3 9 12 15 18 21 24 27 30 33 36 4 16 20 24 28 32 36 40 44 48 5 25 30 35 40 45 50 55 60 6 36 42 48 54 60 66 72 7 49 56 63 70 77 84 8 64 72 80 88 96 9 81 90 99 108 10 100 110 120 11 121 132 12 144
>>> </lang>
Tcl
<lang tcl>puts " x\u2502 1 2 3 4 5 6 7 8 9 10 11 12" puts \u0020\u2500\u2500\u253c[string repeat \u2500 48] for {set i 1} {$i <= 12} {incr i} {
puts -nonewline [format "%3d" $i]\u2502[string repeat " " [expr {$i*4-4}]]
for {set j 1} {$j <= 12} {incr j} {
if {$j >= $i} { puts -nonewline [format "%4d" [expr {$i*$j}]] }
} puts ""
}</lang> Output:
x│ 1 2 3 4 5 6 7 8 9 10 11 12 ──┼──────────────────────────────────────────────── 1│ 1 2 3 4 5 6 7 8 9 10 11 12 2│ 4 6 8 10 12 14 16 18 20 22 24 3│ 9 12 15 18 21 24 27 30 33 36 4│ 16 20 24 28 32 36 40 44 48 5│ 25 30 35 40 45 50 55 60 6│ 36 42 48 54 60 66 72 7│ 49 56 63 70 77 84 8│ 64 72 80 88 96 9│ 81 90 99 108 10│ 100 110 120 11│ 121 132 12│ 144