Prints an inverted pyramid.

inverted_pyramid.sh

#!/usr/bin/env bash
#
#   Inverted Pyramid
#   By: Aaron
#   Date: July 28, 2012
#
#   This script will only accept one argument that should be a number.
#   It will print an upside down pyramid that starts at the nearest odd number to the one you provided.
#
#   Screenshot: http://newroman.net/permalink/inverted_pyramid.png
#
if [ $# = 1 ]
then
	num=$1
else
	echo 'Need one argument'
	exit 1
fi

if [ $num -le 1 ]
then
	echo 'Number too small'
	exit 1
else
	:
fi

if [ `expr $num % 2` -eq 0 ]
then
	num=`expr $num + 1`
else
	:
fi

counter=0
while [ $counter != $num ]
do
	printf "*"
	counter=`expr $counter + 1`
done
printf "\n"
counter=0

spaces=1
while [ $num -gt 1 ]
do
	while [ $spaces != $counter ]
	do
		printf " "
		counter=`expr $counter + 1`
	done
	num=`expr $num - 2`

	counter=0
	while [ $num != $counter ]
	do
		printf "*"
		counter=`expr $counter + 1`
	done

	printf "\n"
	counter=0
	spaces=`expr $spaces + 1`
done