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Everyone I talk to says Goto statements are bad programming but I have yet to figure out a way to return to a line of code that I have passed in the program. The only way I know of to go back up the code is to do this:
A:
blah();
blah();
cout<<"Blah";
goto A;
thats the only way i can think of to go back up to the start, how else would you do it? I know that people use for while loops and such but again, how would you go back up the code? Please help me turn from the dark side.
If it works, go for it.
Its just reading the code becomes difficult when you use goto commands. You dont know where the goto is going and where its come from on big programs.
But to answer your question on alternative solutions there really is a simple one. Loops.
You could use a while loop for that example
char user_selection;
while (user_selection != 'Y')
{
blah();
Blah();
cout << "whatever";
count << "Do you want to continue?"
char = getch();
}
This exits when the user enters in a Y. It loops again otherwise.
> If it works, go for it.
No.
The while loop idea's the right way.
I am extremely thankful to my computer science teacher for not even bothering to grade work with goto statements. goto statements are bad form, and will lead to bad code, and worse, will preclude you from ever getting a serious computer programming job.
Break the habit ASAP, because if you get used to using goto controls, it will just be harder to get into proper structured programming.
Umm, ok, that works for small loops but what if I need to do this:
A:
blah();
blah();
blah();
if (something==something)
goto B;
else
goto A;
B:
blah_blah();
goto A;
how would i make a loop to do that?
Code:while (TRUE) {
blah();
blah();
blah();
if (something==something){
blah_blah();
}
}
If you are trying to go up, think of
{ as the label
} as the goto
ok now what if you are trying to do a selection like:
char sux[9];
cout<<"life sux does it not?";
cin>>sux[9]
if (sux[9]==yes)
{
cout<<"you need some fun in your life go play solitare."
goto solitare;
}
else if (sux[9]==no)
{
cout<<"you are too optimistic. Go play Death march."
goto deathmarch;
}
else
cout<<"your mother raised you well. Lets play Mommasboy."
goto Mommasboy
solitare:
cout<<"blah";
blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah;
deathmarch:
cout<<"die";
die die die die die die die die die die die die die die die die die die die die die die die die;
mommasboy:
cout<<"mommy?"
mommy mommy mommy mommy mommy mommy mommy mommy mommy mommy mommy mommy;
plus does this string comparison work anyways?
> plus does this string comparison work anyways?
No.
And use functions.
I have been corrected for believing this...Quote:
Originally posted by Unregistered
I am extremely thankful to my computer science teacher for not even bothering to grade work with goto statements. goto statements are bad form, and will lead to bad code, and worse, will preclude you from ever getting a serious computer programming job.
Break the habit ASAP, because if you get used to using goto controls, it will just be harder to get into proper structured programming.
For beginners, I agree that its usage can lead to bad code and at that point, time spent strengthening your code structuring skills are more important....
goto does have its attributes in that you can change the flow of the code without the overhead of a condition.......it can be handy for breaking out of deep nested loops in one statment....
I suppose the fact that this statement has survived the test of time and various standard commissions is proof that it has its uses.....
I use goto in small condition cases and ONLY when I HAVE FULL CONTROL or i'm feeling lazy to code.
cout<<"enter month : ";
m1:
cin>>mm;
if(mm>12)
goto m1;
BUT if you can avoid the use of goto it its better.
it leads never ending loops, program crashes, system crashes, angry senior programmers, nuclear attack on your country etc etc.. :p
for the particuar case of repeating the whole program use do-while, its better IMHO than while in this case.
> its better IMHO than while in this case.
Wha...?
Code:cout<<"enter month : ";
m1:
cin>>mm;
if(mm>12)
goto m1;
Code:cout<<"enter month : ";
do
cin>>mm;
while(mm>12);
I knew that somebody will get :confused:
what i meant by "do-while being better IMHO" is the case he 'ESPARANO' asked
Quote:
Umm, ok, that works for small loops but what if I need to do this:
A:
blah();
blah();
blah();
if (something==something)
goto B;
else
goto A;
B:
blah_blah();
goto A;
how would i make a loop to do that?
ans somebody 'UNREGISTERED' replied use while
i prefer using DO-WHILE.
:)
IMHO, if you can't program without goto's, then you can't program. Not to be harsh, but procedural programming should be structured. goto's violate structured programming. I should be able to look at a flowchart of your program and be able to trace a line from beginning to end without having to lift my pencil.
goto's are probably the lamest thing on the planet. continue's are up in the top 10.
while() and do-while() shouldn't be used interchangably. do-while() is usually used for menu systems b/c the code inside the block will be executed AT-LEAST once. A block in a while() loop is never guaranteed to execute.Quote:
Originally posted by ihsir
ans somebody 'UNREGISTERED' replied use while
i prefer using DO-WHILE.
use FUNCTIONS!
Your missing the point.....its not a messure of ability or even preference........occasionally goto will have its uses.....otherwise it would be taken out of the standard.......Quote:
Originally posted by biosx
IMHO, if you can't program without goto's, then you can't program. Not to be harsh, but procedural programming should be structured. goto's violate structured programming. I should be able to look at a flowchart of your program and be able to trace a line from beginning to end without having to lift my pencil.
goto's are probably the lamest thing on the planet. continue's are up in the top 10.
In short, goto is fine in assembly and needed. JMPs are essentially gotos. In C/C++, there is always a better way.
In 18 months of programming, I've never found a use for continue. i know 18 months isn't long but I thought I might have used it by now.Quote:
Originally posted by biosx
goto's are probably the lamest thing on the planet. continue's are up in the top 10.
Btw, I've never used goto either :)
I think this whole qestion on to GOTO or not to GOTO is dumb
I totally agree with
Fordy- goto has its occ uses
Bubba- the whole thing he said
Again i'll repeat.. that the UNREG guy said to use while in the case ESPARNO asked but as you said that DO executes and then chks i suggest that it will be better to use it than while
Also, i think a lot of people just say that gotos shouldn't be used blah blah blah.. to sound :cool: but i have used GOTOs 1000's of times and not encounterd a single problem yet. :)
gotos are needed when you have just typed thousands of lines and you realize you need to repeat somthing