C Programming - Pointers - Discussion

@All.

Here y and z point to the same location and that contains the address of var x and dereferences to value 30.

Then post increment ++ has higher precedence than * this the address of y gets incremented but still. Not assigned to ptr var y as it's post decrement. The updated address is shown only while printing it at the final statement so the address remains the same now similar concept applies to *z++ thus no changes happen inside this statement next x gets incremented this at the final statement we get the incremented value of x i e 31 and the updated address of y and z i.e the postfix operation has come into light only after its use after post increment line.

i.e
Say int x=30 now if I printf("%d",x++);
I still get 30 as it isn't assigned (incremented value ) to var x. It is only after this block finishes execution.
Now again printf("%d",x) and you get the incremented value i.e 31.

*(value of address) and increment/decrement operators lie in the same level of precedence. Their precedence level proceeds in right to left manner.

So, if ++ is to the left of * then * will be evaluated first.

Similarly, (in this case) ++ is to the right of * so y++ is evaluated first. *y++ is same as *(y++) and ++*y is same as ++(*y).

Since they mentioned integer is 4 bytes. If we increment from 500 address it will take next 4th address i.e is 504.

It is already given that size is 4.

As it depends on 16byte or 32byte?

Address size will be 2 byte, then how it can be 504?

It should 502.

#include<stdio.h>

int main()
{
int x=30, *y, *z;
y=&x; /* Assume address of x is 500 and integer is 4 byte size */
z=y; // initialization z by 500
*y++=*z++; // pointer size is 4 byte when we use the increment operater at that time pointer incremented by the pointer size.
x++;
printf("x=%d, y=%d, z=%d\n", x, y, z);
return 0;
}

& deals with the address of the variable mark that point.
So here y=&x
&x means address of x
What is the address of x?
It is 500
So y=500
Point it that the value stored in y is the address of another variable y.

Again it says
Z=y
Z=500
Now,

*y++=*z++
Let's break the term
* in front of the pointer returns the value
Meaning *y point to some other variable
That is
Y=&x
So *y=30
And it needs to be incremented because of
*y++

But if we consider the right side of y assignment
There is *z++
That stores the address 500
And since it has to be incremented
And here address increment must be from 4
That is 504
So here y=z= incremented value that is 504.

*y++=*z++;.

Is above statement means 504=504?

Can anyone tell depending on the size of integer *y++ value will increment by 4?

Here the value of x =30;
We will consider that the address of x is 500;
And very integer have size 4 byte, so that *y++=*z++ are equal having both address value 500 and incremented with one time and value of x is also incremented by one that's why x having 31 and y=z having 504.