SectionA
Write the programs for the following problems in C.
1. Swap two variables x,y without using a temporary variable.
2. Write algorithm for finding the GCD of a number.
3.Write a program for reversing the given string.
4. The integers from 1 to n are stored in an array in a random
��� fashion. but one integer is missing. Write a program to find the
��� missing integer.
Ans): Hint : The sum of n natural numbers is = n(n+1)/2.
�������� if we subtract the above sum from the sum of all the
�������� numbers in the array , the result is nothing but the
�������� missing number.
5. Some bit type of questions has been given on pointers asking to
��� to find whether it is correct from syntax point of view. and if
��� it is correct explain what it will do. (around 15 bits).
�
SectionB
6. For the following C program
#define AND &&
#define ARRANGE (a>25 AND a<50)
main()
{int a = 30;
if (ARRANGE)
printf("within range");
else
printf("out of range");
}
What is the output?
7. For the following C program
#define AREA(x)(3.14*x*x)
main()
{float r1=6.25,r2=2.5,a;
a=AREA(r1);
printf("\n Area of the circle is %f", a);
a=AREA(r2);
printf("\n Area of the circle is %f", a);
}
What is the output?
Ans. Area of the circle is 122.656250
Area of the circle is� 19.625000
8. What do the following statements indicate. Explain.

int(*p)[10]

int*f()

int(*pf)()

int*p[10]
Refer to:
 Kernighan & Ritchie page no. 122
 Schaum series page no. 323
9. Write a C program to find whether a stack is progressing in forward
��� or reverse direction.
10. Write a C program that reverses the linked list.
�