swapping c and d variables
$ c = $ c + $ d ; $ d = $ c - $ d ; $ c = $ c - $ d ; echo " values ▁ after ▁ swapping ▁ are ▁ : ▁ " , " STRNEWLINE " ; echo " a = " ▁ , ▁ $ a ▁ , " " ; STRNEWLINE echo ▁ " b = " ▁ , ▁ $ b ▁ , " " ; STRNEWLINE echo ▁ " c = " ▁ , $ c ▁ , " " ; STRNEWLINE echo ▁ " d = " ▁ , ▁ $ d ▁ , " " }