What output will be generated by the given code d\segment if:

Line 1 is replaced by “auto int a = 1;”

Line 2 is replaced by “register int a = 2;”

(A) 3 1

4 1

4 2

(B) 4 2

6 1

6 1

(C) 4 2

6 2

2 0

(D) 4 2

4 2

2 0

Answer (D)

If we replace line 1 by “auto int a = 1;” and line 2 by “register int a = 2;”, then ‘a’ becomes non-static in prtFun(). The output of first prtFun() remains same. But, the output of second prtFun() call is changed as a new instance of ‘a’ is created in second call. So “4 2” is printed again. Finally, the printf() in main will print “2 0”. Making ‘a’ a register variable won’t change anything in output.

Line 1 is replaced by “auto int a = 1;”
Line 2 is replaced by “register int a = 2;”
(A) 3 1
4 1
4 2
(B) 4 2
6 1
6 1
(C) 4 2
6 2
2 0
(D) 4 2
4 2
2 0

Answer (D)
If we replace line 1 by “auto int a = 1;” and line 2 by “register int a = 2;”, then ‘a’ becomes non-static in prtFun(). The output of first prtFun() remains same. But, the output of second prtFun() call is changed as a new instance of ‘a’ is created in second call. So “4 2” is printed again. Finally, the printf() in main will print “2 0”. Making ‘a’ a register variable won’t change anything in output.