Is there any any method to close single line comment?

Answer 1

You can't close single line comment but you can use multi lines comments in a single line like this :

std::cout /*we are going to output*/ << /* something */ "Like that" << std::endl /*(don't forget the semicolon ^^)*/; //and a single line comment you can not close !

Edit:
if you want a single line comments that begins at the end of the line so in fact there is no need to close it as said by Pixie but if you just want to insert comments in one line between expressions, using multiline comments can be a solution.

Answer 2

No.
There isnt a need to close a single line comment tho

Answer 3

No as a single line comment lasts to the end of line