• C

# struct and real type

typedef struct buzz {
int a;
int b;
} strtype;

...........
...........

strtype num={142,2804};
// a=142
// b=2804
// c=142.2804
how can i convert to a and b ande merge them c;
with using a function.

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Commented:
In C and C++, the fields of a structure are referenced via the . operator, e.g.

srtype num = {142, 2804};
int a = num.a;
int b = num.b;
int sumAB  = a + b;   /* or = num.a + num. b */

In this case, you haven't defined what you mean by "merge."  It appears that what you want is:

double c = a + (0.0001 * b);

but even this isn't quite right, because it hardwired the multiplier.  Chances are you really want to calculate this based on the size of num.b.  To do this, you need to calculate the number of digits in num.b (easy to do using the floor and log10 functions, or manually by dividing by 10.0 until the result is less than 1.0 and counting the number of iterations), and then divide num.b by 10.0 to that number plus 1.  The tricky part is keeping track of which calculations need to be floating point and which need to be integral.   I'm omitting the actual formula because this sounds too much like homework.

As for doing it via a function, functions can take structs as parameters and return doubles or float as results.  In this case, you can choose to pass the struct by value (because it's small enough not to matter) or by address.  If you pass it by address, then there's a syntactic shortcut for referring to the fields, using p->fieldname instead of having to use (*p).fieldname.  For example,

double someFunction(strtype* pSomeStruct) {
int a  = someStruct->a;
....
}

Gary

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