The document compares computers to dumbo, explaining that both require input from a user to perform tasks. It then provides details about C++ programs, data types used in C++ like int, float, double, char, and string to store different types of data. It explains concepts like binary representation of numbers, operators and precedence, loops, structures, and pointers. Overall, the document covers fundamental concepts about how computers work and common data types and programming elements used in C++.

3.  Here is a man dumbo which do not perform task
by himself. So we have to give him command and
then he will perform it.
 Similarly , the computer also can’t perform task by
himself until we give him some set of instruction
to perform(command).
 So, computer take some INPUT form user perform
some COMPUTATION then give useful
INFORMATION or DATA.
COMPARING DUMBO WITH
COMPUTER :

4. #include <iostream>
using namespace std;
int main()
{
/* program code */
return 0;
}

5. A modern-style C++ program that uses the new-style
headers and a namespace -
#include <iostream>
using namespace std;
int main()
{
/* program code */
return 0;
}

6.  The new-style headers do not specify filenames.
 They simply specify standard identifiers that might
be mapped to files by the compiler, but they need
not be.
 <iostream>
 <vector>
 <string>, not related with <string.h>
 <cmath>, C++ version of <math.h>
 <cstring>, C++ version of <string.h>
 Programmer defined header files should end in “.h”.

8. •Computer consist of:
•Main Memory
•Registers
•ALU
•Input
•Output devices
•Disk
•Bus ,etc .
•NOTE: The data is always copied if we take any variable (data)
and perform some operation on it. So there will we always a
GARBAGE VALUE present at address or memory location.
•Computer uses only binary language to perform ANY task or to
store any data.

9.  In c++ we can use int data type to store a integer
value.
 Int uses 4 byte or 2 byte to store data.
 There are some data type which are used with in to
store data which required less or more storage,
they are:
 Short-2byte
 long-8byte
 unsigned-numbers with positive values only.
 Range = -2^31 to 2^31-1

10. Example: data type – int – size=4byte(32bits)
Formula:
1.)For signed -2^n to 2^n-1 .
2.)For unsigned 0 to 2^2n -1 .
Here n=number of bits.
n= 32,
-2^32 to 2^32-1 or
0 to 2^64-1 .

11. •In computer the signed interger is stored in
the form of binary numbers.
•The positive numbers from 0 to infinity the
number will be in its complement form.
• The MSB will 0 for positive and 1 for
negative.
•The remaining part of negative number will be
in its 2’s complement.

12. 1. If the number is starting with 0 then the
number will be in octal.
2. If the number is starting with 0x then the
number will be in hexadecimal.
3. We can define a constant by using const.

13. •To represent floating numbers in c++ the float
and double data types are used .
•Float – 4byte – 7 digits.
•Double – 8byte – 15 digits.

15. •To represent string there are three data types
available in c++, they are:
•1. string
•2. char
•3. bool (true or false).
•For every character there is a ASCII value
•E.g. : ‘A’=65 , ‘a’ =97 , ‘0’ =48 etc.
•Range of char= 0 to 255.
•E.g. : char x=‘a’ ;

16. •In string data type the string “harsh” will be
stored in the from of array .
•E.g. : string =“HARSH”;
•Also,
•E.g. : char arr[6]=“HARSH”;
•Here ‘0’ is the NULL string which signify the
end of the string.
•In boolean, bool data type store only true-1 or
false-0.
H A R S H 0

17. #include directives
int main()
{
constant declarations;
variable declarations;
executable statements;
return 0;
}

18. •Compiler directive or Header file : Instruction
to compiler used when compiling our program
to machine language.
•For e.g. iostream , math, etc.
•Using namespace std : every declaration in the
program is stored in a namespace called “std”.
•E.g. std:: name; if declaration is of name.
•We can also our own namespace , when
required.

19. •Is state that the value(result) of arithmetic
operation depend on more expressive variable.
•E.g. : float a,b;
c=a+b; will be float.
c=a-b; will be float.
c=a/b; will be float……..,etc.
Similarly, 2-2.0 will be float.

20. Precedence : Operator :
1. ( )
2. *
3. + or -
4. / or %
NOTE : Do not use [] or {} rather than of ().
E.g. : a+b*c/d-e == (a+((b*c)/d))-e

21.  Escape character ----- ‘’.
•It is use to escape the use of a character if we
put ‘’ in front of a character then the value is
escaped.
•Like if we want to print “ on console then we
have to use ” .
•Similarly , ,etc.
•Also to print % on console we have to use
%%.

22. Precedence : Operators:
1. !
2. < , <= , > , >=
3. == , !=
4. &&
5. ||

23. •In for( ) or while( ) loop : if there is nothing
then it will assume 1 means it will run the
content of for or while loop.
•For E.g. for(i =0 ; ; i++) ,while( ) ,etc.
•In C++, we can use static members inside a
structure i.e., struct .
•We can also print the address on printf
statement like, printf(“%p”, ” hello world”);
This will print the address on the string.