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Hey Everyone,
Just began programming C and am working through the 'white bible'. Have programmed in LISP and Java prior to this. I have a question regarding the incrementer operator and its usage with arrays. Ex:
What exactly is being incremented here?Code:value = ++myarray[maxvalue - 1];
I haven't seen an increment operator used in this way before!
Cheers
BIOS
You are incrementing the value at myarray[maxvalue -1] and then assigning it to the variable value.
For example:
myarray[2] is 3 (remember C arrays index from 0, not 1)Code:int myarray[4] = {1,2,3,4}
x = ++myarray[2];
3 + 1 equals 4 myarray[2] ends up being 4
assigning to x makes it 4
(I sometimes find it helpful to substitute real numbers for the variables as a way to understand things)
Hey thanks for the reply!
That makes perfect sense. Thanks for the explanation. I think it was the fact that you can place the increment operator as a prefix in C that threw me. I.e. in Java you would write:
Code:myarray[x]++;
C has both prefix and postfix in this case... The difference being this...Quote:
Originally Posted by BIOS
The difference is whether myarray[2] is incremented before the assignment or after...Code:int myarray[4] = {1,2,3,4}
x = ++myarray[2]; // x = 4, myarray[2] = 4
x = myarray[2]++; // x =3, myarray[2] = 4
Also let me toss in just a small note of caution here... Beware of comparing languages! ... Java does a lot of babysitting that C does not, it also has features C does not. C gives you control over code that is hidden in Java, it can also do some stuff Java cannot... Whenever possible, you should treat your C learning experience as something entirely new and different...
Interesting! I had been wondering why C allowed this.Quote:
Originally Posted by CommonTater
This is great advice. Actually the reason I'm learning C is for this extra control and the greater awareness it brings with regard to managing memory etc. I must remember not to fall into that 'comparison' trap! Thanks alot.Quote:
Originally Posted by CommonTater
One thing I can promise you... C will make you a very careful programmer. Almost everything is on you to get it right.Quote:
Originally Posted by BIOS
(But I wouldn't have it any other way :D )
Considering my troubles understand C/C++ pointer concepts (one could say I am just stupid :) ) I have come to the conclusion that those languages were made by masochists for masochists :PQuote:
Originally Posted by CommonTater
Ok... start a thread for pointers, show us some code... we'll see what we can do.Quote:
Originally Posted by Eman
I assume you don't visit the C++ forum much, I have posted several pointer questions but most related to polymorphism...getting clearer though.Quote:
Originally Posted by CommonTater
Btw, how goes your learning C++?
I read the C++ section but rarely post there. Since I gave up on C++ entirely --it just doesn't make any sense to me-- it doesn't seem right that I should post there... well, except maybe to ask questions.Quote:
Originally Posted by Eman
And here I thought I was the only one. The only reason I am learning it is for the sake of learning it..some say it will make sense when I start working. I hope they're bloody right. Java is even worse.Quote:
Originally Posted by CommonTater
Hopefully, you will go back to it one day man :)
AFAIK Java also have both post and pre increment operators, which also change the operator precedence related to the assignment operator.
Yes, it does..But I was talking about the OOP style in java..Everything is OOP and it takes a while to find what I need. I hate it..
If you have a string you can't modify a character in the string for example. I have to look for some other class. I hate that language..
I was referring to post #3, I should have made a quote to that post, sorry for the confusion. :)Quote:
Originally Posted by Eman