Structure Variables within C language

[Mehr]

I am begginr programmer wiyh C. I want to do a work with structure variables, but I don't know how. Could anyone help me?
I have to define a structure variable like bellow:

struct name{
int x;
int y;
}NAME;

I creat some NAME[i] within a loop and set "x" and "y" for all of them (for example 100 NAME[i]). I must also add that the "y" is a unrepeatable number and in all NAME[i] variales (i.e. there are 100 different "y"). After that I get a number (k) equal to one "y" of the NAME variables within another part of my code. I want with this number (k) get the related x (that its "y" is equivalent to this number).
My problem is that I don't know how can I do that?

Thanks in advance,

Cheers

[RobRussell]

Well to start with, all caps (like NAME) is usually a precompiler constant in C, so you should use something like Name or name_s to represent that struct.

To your problem, you'll need a loop like for() or while(). You'll want to declare an array of your structure large enough to hold them all. I'm not sure what you mean about k, but if you post some code or pseudocode that gives a better idea then maybe others can help more.

[Mehr]

Hi,
Thank you for your reply.
My problem is that I don't want to use any loop for this issue, because the code will become very time consuming. I like to get a method through C that it can give me directly an apropriate NAME that its "y" is equal to my arbitrary number (for example k).

[RobRussell]

Well if your data is sorted you could look at bsearch().

[primeSo]

I am begginr programmer wiyh C. I want to do a work with structure variables, but I don't know how. Could anyone help me?
I have to define a structure variable like bellow:

struct name{
int x;
int y;
}NAME;

I creat some NAME[i] within a loop and set "x" and "y" for all of them (for example 100 NAME[i]). I must also add that the "y" is a unrepeatable number and in all NAME[i] variales (i.e. there are 100 different "y"). After that I get a number (k) equal to one "y" of the NAME variables within another part of my code. I want with this number (k) get the related x (that its "y" is equivalent to this number).
My problem is that I don't know how can I do that?

Thanks in advance,

Cheers

Hi. I was confused by your question at the first place.
You mean you wanted to create 100 instances of your structure called "NAME" is it ? Hope i am not mistaken. Well , the way to create a collection of variable with the type "NAME" should be as below:

NAME nameArray[100];

But the proper way to create a user define data type in C should be as follow:

Name nameArray[100];

. The above code create an array which can store 100 instances or variable of the user define type "NAME". Then your initialize the data member in each member of nameArray[] by using a loop. Note that each member of nameArray[] is indeed a structure that contain 1 integer type call "x" and 1 integer type call "y".

You have mentioned that you want to assign unique number to integer variable y in each variable of NAME type. U didn't mention the expected value of "x". Thus, my suggested method for your question is:
Create N number of variable NAME type and store them in an array as mentioned.
Then, initialize the variable using a for loop.

for( i = 0 ; i < 100; i ++) {
   NAME [i].y = i;
   NAME[i].x = i * i; /* i time i*/
 }

By using the for loop, u assign a unique number to y and i x i to x. Note the dot operator (.) is used to access each member in every variable of type NAME. After the initilization , you could found your corresponding x by searching the corresponding y using a driver program.
You may need to do some reading on the structure.
I don't understand what do u mean by "not using loop". Then u have to use a sequential way to initialize the value of x and y.

[primeSo]

Hi,
Thank you for your reply.
My problem is that I don't want to use any loop for this issue, because the code will become very time consuming. I like to get a method through C that it can give me directly an apropriate NAME that its "y" is equal to my arbitrary number (for example k).

Don't understand your problem.
using loop is time consuming ? u mean the system wise ? not efficient ? C is a structure programming, there are only 4 ways to control the sequence to execute the program. 1 ) Sequence 2) Iteration 3)Select statement 4)Function call.

Try to do some reading , it would help a lot.