The document discusses type definitions in C using typedef, macro definitions using #define, and conditional compilation using #if and #ifdef. It provides examples of typedef to define a new type name SavingsAccount. It also shows examples of #define to define constants like PI and its scope. Further, it demonstrates usage of #if and #ifdef with defined macros to conditionally compile code blocks.

2.  Primitive Syntax :
 typedef existing-type new-name ;
 Examples:

4. Is this correct / valid?
How do I type define an String

10.  In the above declaration, SavingsAccount is
an Variable or Typedefinition?.

12.  P1 is pointer to const
 P2 is constant pointer
 P3 is constant pointer
 P4 is constant pointer

13. int main( )
{
#define PI 3.14
int r = 3;
float area = PI * r * r;
printf(" %f",area);
}

14. void calculateArea( );
int main( )
{
#define PI 3.14
calculateArea( );
}
void calculateArea( )
{
int r = 3;
float area = PI * r * r;
printf(" %f",area);
}

15. void calculateArea( );
int main( )
{
#define PI 3.14
int r = 3;
float area = PI * r * r;
printf(" %f",area);
calculateArea( );
}
void calculateArea( )
{
int r = 3;
float area = PI * r * r;
printf(" %f",area);
}

16. void calculateArea( );
int main( )
{
#define PI 3.14
int r = 3;
float area = PI * r * r;
printf(" %f",area);
#undef PI
calculateArea( );
}
void calculateArea( )
{
int r = 3;
float area = PI * r * r;
printf(" %f",area);
}
void calculateArea( );
int main( )
{
#define PI 3.14
int r = 3;
float area = PI * r * r;
printf(" %f",area);
calculateArea( );
#undef PI
}
void calculateArea( )
{
int r = 3;
float area = PI * r * r;
printf(" %f",area);
}

17. 1. int main( )
2. {
3. int a = 5;
4. if( a )
5. printf(“if executed");
6. #if (a)
7. printf("#if executed");
8. #endif
9. }
a) Compilation Error in Line 6
b) Both printf are executed
c) Only the first pf is executed

18. 1. #define a 0
2. int main( )
3. {
4. if( a )
5. {
6. #ifdef a
7. printf(“A")
8. #endif
9. }
10. }
a) No Error, No Output
b) Error in printf - ; missing
1. #define a 0
2. int main( )
3. {
4. if( a )
5. {
6. #if a
7. printf(“A")
8. #endif
9. }
10. }

20. #define MAYUR 0
int main( )
{
#if MAYUR
printf("#if executed");
#endif
#ifdef MAYUR
printf("#ifdef executed");
#endif
}

21. int main( )
{
#ifdef MAYUR
printf("#ifdef executed");
#endif
}
gcc file.c -DMAYUR