This code can be neatened up a bit, but it works:
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#!/bin/bash
STACK="abc"
MAX_DEPTH=3
DEPTH=0
TOT=0
declare -a STUMP ITERATOR
ITERATOR[$DEPTH]=0
while [ $DEPTH -lt $MAX_DEPTH ]
do
let TOT++
COUNT=0
STRING=""
while [ $COUNT -le $DEPTH ]
do
STRING="${STRING}${STACK:${ITERATOR[$COUNT]}:1}"
let COUNT++
done
printf "%7s: %s\n" $TOT "${STRING}"
COUNT=$DEPTH
LAST=0
while [ $COUNT -ge 0 ]
do
if [ ${ITERATOR[$COUNT]} -eq $((${#STACK} - 1)) ]
then
ITERATOR[$COUNT]=0
else
LAST=1
let ITERATOR[$COUNT]++
continue 2
fi
let COUNT--
done
if [ $LAST == 0 ]
then
let DEPTH++
ITERATOR[$DEPTH]=0
fi
done
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One long-haired git at your service...
