$j=1;print$"x--$h,$_-1?map(rand>$f?"=":qw(
0 @ * +)[rand 4],1..($j+=2)):"*",$/for 1..$h

##</code><code>##

print$"x--$h,$_-1?map(rand>
$f?"=":qw(0 @ * +)[rand 4],
1..($j+=2)):"*",$/for++$j..$h

##</code><code>##

print$"x--$h,$_-1?map rand>
$f?"=":qw(0 @ * +)[rand 4],
2..$_*2:"*",$/for 1..$h