ISRO2015-70

Question

The following program

main()
{
    inc(); inc(); inc();
}
inc()
{
    static int x;
    printf("%d", ++x);
}

• A. prints 012
• B. prints 123
• C. prints 3 consecutive, but unpredictable numbers
• D. prints 111

Answer 1

answer is B)

As static is implicitly initialized to 0

and inc() is called 3 times

hence output will be 1,2,3

Comments

its a static variable .... and static variables use the same copy of varible for  every function....

---

isn't it true that it is not recommended to do increment or decrement in printf statement as doing this would lead to a compiler dependent output??
therefore option C is true;
or the Static variable is creating any difference here

---

There's nothing like that in C.

Answer 2

Answer (B)

x is static so during initialization it's value is 0,with every call it increases by 1

first call = 0+1 =1

second call= 1+1=2

third call = 2+1 = 3

so 123 is printed

Answer 3

Important points about the static variables:- 

• They're initialised right at the start, and their value are stored inside the Runtime Environment.
• Once initialised, they're never initialised again.
• If in the beginning, value is not assigned for initialisation, then it is assigned 0 by default.

    static int x;

Value assigned 0 implicitly. So, x = 0.

Combine this fact with pre-increment, we get option B