C Programming Questions with Explanation

Q:: What will be the output::
void main()
{
          int x;
          scanf("%d",&x);
          if((x)&&(!x))
               printf("Hello");
          if((x)||(!x))
               printf("World");
}
(A) HelloWorld                                                       (B) World
(C)Hello                                                                  (D) Depends upon value of 'x'

Ans:: (B)

Explanation::

In C programming the logical not operator performs the complement operation i.e. it converts a condition from true to false or false to true. In other words it converts a non-zero number to zero and zero to one.

So the first 'if' will always be false and the second 'if' always be true.