whohas

#!/bin/bash

A=({2..26})
E=({27..51})
F=({52..76})
ET=({77..100})

while getopts ':f:p:' OPTION; do
  case "$OPTION" in
    f)
      classroom="${OPTARG^^}[@]"
      ;;
    p)
      prog="$OPTARG"
      ;;
    :)
      echo "Missing argument for $OPTARG" >&2
      exit 2
      ;;
    ?)
      echo "Invalid flag." >&2
      exit 2
      ;;
  esac
done

if [[ "$prog" ]] && [[ "$classroom" ]]; then
  for i in "${!classroom}"; do
    pc=159.59.9.$i
    if ping -c 1 $pc >/dev/null; then
      echo "Checking if '${prog}' is in $pc."
      ssh root@$pc "which ${prog}"
      echo
    else
      echo "$pc is off."
    fi
  done
else
  echo "Missing some argument in the script." >&2
  exit 2
fi