sum != gcd checks that both the numbers are positive or not
if ( __gcd ( $ gcd , $ sum - $ gcd ) == $ gcd && $ sum != $ gcd ) echo " a = " ▁ , ▁ min ( $ gcd , ▁ $ sum ▁ - ▁ $ gcd ) , STRNEWLINE " b = " else echo ( -1 ) ; }