if ! [[ {$1 = *.txt || $1 = "-n" || $1 = "-p"} && {$2 = "-n" || $2 = "-p" || $2 = *.txt || $2 =~ "^-?[0-9]+$"} &&
 {$3 = *.txt && $3 = "-p" && $3 =~ "^-?[0-9]+$"} && $4 != *.txt ]]; then
    echo "Napaka: neznano stikalo." && exit 0
fi