Blizzhackers

im a few days into learning my first programing language...C++. i wrote a very basic console application to see what i could do...it was originally part of the book i was using and i took it a step farther and then another step farther and so on...basically im stuck trying to get the program to loop. at the beginning of the program the user has to enter a value and after several if statments it displays some text depening on the inputed value. i want to insert a sort of "would you like to do this again? Y/N. type function where Y would start the program at the entering the first value...i used a goto loop: statment and placed loop: at the before the first int is declared. problem is it loops using the already entered ...i want the user to have to enter another int

sort of like

Edit by Gorthal: code tags

Try using code tags next time. Anyway, using goto is bad practice (why, I don't know, but whatever). You'll want to do something more like:



Not entirely sure if the break will break the for or just the while. You'll have to play with it. Typed it up in about 2 minutes, so good luck. Honestly, this could be coded a lot better, but it's 5:30 am.

How old is that book? You should not use goto to create loops that's an ancient way.
Rather you should use goto to escape deeply nested loops or to free memory.



or take an "if wall" as another example.



Then have a short read
http://www.cs.utexas.edu/users/EWD/ewd02xx/EWD215.PDF

goto isn't any different than jmp label, so I don't see how it is "bad", I just know it isn't "good practice".

every single major compiler turns loops into labels, and in fact goto can be used for optimization (threaded-execution). It was considered bad because it can lead to memory leaks and it could lead to destructors not being called (due to jumping out of scope), but now the former is solved with smart pointers, and the latter is sovled but it being treated as a bug by compilers (so it can't compile). Apart from that, it just makes readability difficult if overused.

if you are nesting deeply enough to warrant goto, you should consider refactoring first (makes things more manageable, and more readable).

Of course there are more elegant solutions but it's just a simple example where a goto is useful.

Personally, I have never needed to use goto in C++. It has it's uses in C for cleanup and exception emulation but C++ has those things built in already. There is nothing inherently wrong with using goto if you are aware of the limitations, it's just that there almost always (in my opinion) a more elegant solution.

@FireFromTheSky: break and continue only work on the innermost loop.

Back in CS1 Freshman year I used a goto in a c++ application. My prof docked me like 10 points and wrote "There is only one acceptable use for goto.. and this is not it."

I still don't know what the acceptable use is..

that makes me giggle

/e mostly because my programming teacher in high school was also my e-commerce teacher, he obviously never read anything I wrote in that class I would in mid sentence write things like "and the little balloon flew high into the sky" or "meow meow meow meow meow meow". 100% on everything.

Ha, thats my uni,,, and my prof just assigned us to read that paper.