Can you write a program that prints its own source code ( in C/C++ )? Of course it would be easy to do that referring to the source file, but how can this program be written assuming that the souce file is not available at run time?
:?: :?:
vicky_dev
12
Junior Poster in Training
Recommended Answers
Jump to PostSuch a program is known as a 'Quine' - see here for more info http://en.wikipedia.org/wiki/Quine_%28computing%29
Jump to PostIt can't.
It's proven that in any Turing-complete language you can create a program that writes its own code as output.
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WaltP
2,905
Posting Sage w/ dash of thyme
Team Colleague
It can't.
bala24
5
Junior Poster
An old one..
Hope this is what u looking for
char*s="char*s=%c%s%c;main(){printf(s,34,s,34);}";
main()
{
printf(s,34,s,34);
}These are called signature programs by the way..
Bench
212
Posting Pro
Such a program is known as a 'Quine' - see here for more info http://en.wikipedia.org/wiki/Quine_%28computing%29
Salem
commented:
Beat me to it - Salem
+4
John A
1,896
Vampirical Lurker
Team Colleague
And if you compile a program in a compiler's debug mode, it compiles the source code into the resulting executable file. I assume using some process in the program, you would be able to extract the source code (although I could be wrong).
[edit] My 1000th post
Rashakil Fol
978
Super Senior Demiposter
Team Colleague
It can't.
It's proven that in any Turing-complete language you can create a program that writes its own code as output.
SpS
commented:
Yup
+3
iamthwee
It's proven that in any Turing-complete language you can create a program that writes its own code as output.
Yeah. My guess is Mr Disney was trying to be smart... should have googled first before making assumptions. Ha ha.
~s.o.s~
commented:
:(
-2
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