#!/bin/sh
if [ $# -ne 1 ]
then 
  echo "usage: square Num" >&2 
  exit 1
fi

count=0

if [ $1 -ge 0 ]
then
  while [ $count -le $1 ]
  do
    sq=`expr $count \* $count`
    echo $count $sq
    count=`expr $count + 1`
  done
else
  while [ $count -ge $1 ]
  do
    sq=`expr $count \* $count`
    echo $count $sq
    count=`expr $count - 1`
  done
fi