Gate Sample Question

Question

int f(int n)
{
    static int i = 1;
    if (n ≥ 5)
        return n;
    n = n + i;
    i++;
    return f(n);
}

The value returned by f(1) is:
(a) 5 (b) 6
(c) 7 (d) 8

 

need solution with explaination

Answer 1

Static storage class allows to initialize a variable for one time and re-initialization can't be done till end of program 

execution of f(1)

i=1

n=2

i=2

call f(2)

i=2

n=4

i=3

call f(3)

i=3

n=7

i=4

call f(7)

since n >= 5 so return n(7)

Answer 2

yeah the question is correct. Here the static initialization is executed only once through out the execution of program.so i is intialized to 1 only once and then it keeps on increasing its value.in

1 step- f(1) since n =1,it gets incremented by i.i.e n=2.then i++ makes i=2.

2 step-f(2)since n=2,it gets incremented by i(.i.e n=2+2.)then i++ makes i=3.

3 step-f(4)since n=4,it gets incremented by i(.i.e n=4+3.)then i++ makes i=4.

4 step-f(7)since n>=5 is satisfied returns n value. i.e->n=7

so answer is 7