Showing my program is wrong but it is correct

#1

I have run my program by providing custom input and output is absolutely correct then too not a single test case is passed.

#2

your order of the output is not correct
your answer:
a b ab c ac bc abc d ad bd abd cd acd bcd abcd
correct:
d c cd b bd bc bcd a ad ac acd ab abd abc abcd

#3

but only the sequence is different only all components are same

#4

yes, to pass the test cases you need to print according to the required output format