#!/bin/sh
sum=0
for i in $*
do 
	sum=$[$sum+$i]
done
ave=$[$sum/$#]
echo "average=$ave"

#!/bin/sh
sum=0
all=$#
until [ $# -eq 0 ]
do
	sum=$[$sum + $1]
	shift
done
ave=$[$sum/$all]
echo "average=$ave"

#!/bin/sh
sum=0
all=$#
while [ $# -gt 0 ]
do 
	sum=$[$sum+$1]
	shift
done
ave=$[$sum/$all]
echo "average=$ave"

#!/bin/sh

for f in ./$1/*
do 
	if [ ! -s $f ]; then
		rm -f $f 
		echo "deleted $f"
	else
		echo ""
	fi
done

#!/bin/sh
sum=0
echo "$sum"
for i in $*
do 
	echo "+$i"
	sum=$[$sum+$i]
done
echo "------"
echo "=$sum"
 

#!/bin/sh
sum=0
echo "$sum"
until [ $# -eq 0 ]
do
	sum=$[$sum + $1]
	echo "+$1"
	shift
done
echo "------"
echo "$sum"
 

#!/bin/sh
sum=0
echo "$sum"
while [ $# -gt 0 ]
do 
	sum=$[$sum+$1]
	echo "+$1"
	shift
done
echo "------"
echo "$sum"