read -n1 a
set 12_9a9a3a9b9b3b9c9c3c9d3d 3_9a9a3a9b9b3b9c9c3c9e3{f..h}
((a-6))||set 3_5a5b5c5d5e5f5g5h5i5j5k5l5m3n 1_5a5b5c5d5e5f5g5h5i5j5k5l5m2o1{p,q}
((a-1))||set 12_9a3a 12_9b3b 2_2c2d2e2f2g2h
for c;{
for((d=${c/_*};d--;)){
e=${c/*_}
for((;${#e};));{
for((f=${e::1};f--;));{
printf ${e:1:1}
}
e=${e:2}
}
echo
}
}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).