#! /bin/sh

if
  [ "$1" = "--help" -o $# -eq 0 ] #Ha "--help" az elso parameter vagy (-o) nincs parameter
then
  echo Usage: 2feladat.sh a b c
  exit 0
elif
  [ $# -gt 3 ]
then
  echo Too many parameters! \($#\) Exiting...
  exit 1
elif
  [ $# -lt 3 ]
then
  echo Too few parameters! \($#\) Exiting...
  exit 2
else

for i in $@
do
  if [ "$i" -le 0 ]
  then
    echo No negative numbers allowed!
    exit 3
  fi
done

if [ `expr $1 + $2` -le $3 -o `expr $2 + $3` -le $1 -o `expr $1 + $3` -le $2 ]
then
  echo Not a valid triangle!
  exit 4
fi

let result=$1+$2+$3
echo $result
fi