Winsome Publication: Computer Concept & Programming In C - Unit I

Q.9. Write a C program to swap two integer variable without using third variable. (2009-10)

Ans. /* A program to swap two integer variables without using third variable */

# include < stdio.h>

# include < conio.h>

void main ( )

{

int a, b;

clrscr ( );

printf (“\n Enter 1st number”);

scanf (“% d”, & a);

printf (“\n Enter 2nd number”);

scanf (“% d”, & b);

a = a + b;

b = a - b;

a = a - b;

printf / “\n The number after swapping:”);

printf (“\n 1st number % d”, a);

printf (“\n 2nd number % d”, b);

getch ( );

}

Q.10 What do you understand by digital computers? Explain components of a digital computer with the help of block diagram.

Related Questions -

Q. Define digital computer. List the basic operations performed by computer.
(AKTU. 2013-14)

Q. Draw a neat schematic of a digital computer and explain the role of each functional unit. (AKTU. 2010-11)

Q. Explain the role of control unit of CPU in computer system. (AKTU. 2012 - 13)

Ans. Digital computers: -

A digital computer is a digital information processing system.

The general-purpose digital computer is the best-known example of the digital function.
Digits are discrete elements in the early computer design.
The term digital computers thus emerged.
Discrete elements of information are represented by physical quantities called signals.
Voltages and currents are the most common electrical signals.
Binary signals are the most popular digital signals in modern electronic digital systems. Two discrete values are (high/low), (true/false), (1/0).
A binary digit is called a bit.

The block diagram of a digital computer is