## How to Contribute to Odia Wikisource - ଓଡ଼ିଆ ଉଇକିପାଠାଗାରରେ କେମିତି ଯୋଗ ଦେବେ

Do you know how to contribute to Odia Wikisource? Here is a basic video on Odia Wikisource, its requirement, and some basic ideas on how to contribute to the Wikisource Project.

Wikisource – The Free Library is a Wikimedia Foundation project to create a growing free content library of source texts, as well as translations of source texts in any language.

The main aim of this project is to preserve the old books, documents, newspapers in digital format which would available for all in creative commons license.

In October 2014, Odia Wikisource started, and initially, lots of people joined hands and helped to type, proofread, and validate the Odia Bhagabata, as a result, whole parts of Bhagabata written by Jagannath Das is available on the Internet with Odia Unicode scripts.

Here is the video on our YouTube Channel, which you could watch for a better understanding of Odia Wikisource and some basic steps which a new contributor to follow to join this noble work.

## Operators in C Program • Operators are the symbols used between two operands to perform a particular operation.
• Operators are used to perform logical and mathematical operations in C Programming.
• The operators join individual constants and variables to form expression.
• Operators, Functions, Constants and Variables combined together to form expressions.
• Let's take an example- a * b + c
• Here * and + are the Operators.
• 'a', 'b' and 'c' are the variables and we could take some constants.
• Here the variable and constants are called as Operands.
• All are combined to form an expression.
• In general, we could divide the operator into three types as;
1. Unary Operator
2. Binary Operator
3. Ternary Operator
• But as per our use, we could divide the operators into the following types;
1. Arithmetic Operator
2. Assignment Operator
3. Relational Operator
4. Logical Operator
5. Conditional Operator
6. Bitwise Operator
7. Increment/Decrement Operator
8. Special Operator

### Unary Operator

• The operator which act on single operand is known as Unary Operator.
• It takes only one operand.
• It is used to define the +ve and -ve values with the signs like + or-.
• Ex: -a, -b, -3, +5, etc.
• We won't use the + symbol before any positive number, so we usually write the value only.
• Increment/Decrement operators are Unary operators.
• Ex: --a, ++b, etc;

### Binary Operator

• The operators which act on two operands is known as Binary Operator.
• It takes two operands.
• All the 2nd type of operators list described above are considered as binary type except Increment/Decrement operator.

### Ternary Operator

• The operators which act on three operands is known as Ternary Operator.
• Ex: a?b:c
• The expression in the example is called as Conditional Operator.
• Here 'a' is the expression and 'b' is the true statement and 'c' is the false statement.
• Syntax- (expression)?true statement:false statement;
• Ex: (a>18)?printf("Eligible to caste for vote."):printf("No eligible for caste.")

#### 1. Arithmetic Operator

• These operators are used for the basic and common mathematical operations like addition, subtraction, multiplication, division etc.
• Operators are:
• + : Addition Operator
• - : Subtraction Operator
• * : Multiplication Operator
• / : Division Operator
• % : Modulus Operator
• The modulus operator is always applicable for the integer.
• In the modulus operator, the operator sign will depend always on the sign of the 1st operand.
• ^ : Caret or Power
• Ex: 3^2 = 32

#### 2. Assignment Operator

• Assignment operators are used to for assigning a variable to a value.
• Mainly the '=' symbol is used for assigning.
• x=2;
• Here 2 is assigned to the variable x.
• x+=2;
• It means x=x+2;
•  We could use x-=2; for x=x-2; and so on for others.

#### 3. Relational Operator

• Relational operators are used to compare the relationship between two operands.
• < : Less than Greater than Less than or equals to Greater than or equals to Equals to Not equals
• The relational operator returns true of false value.

#### 4. Logical Operator

• Logical operators are used to perform the logical operations.
• && : Logical AND Logical OR Logical NOT Logical NAND Logical NOR

#### 5. Conditional Operator

• The conditional operators are used to check whether a given condition is true or false and generate the statement accordingly.
• The conditional operator is the Ternary operator.
• The syntax is:
• (condition)?true statement:false statement;
• If the given condition would true, then the true statement would generate and if not, then the false statement would generate.

#### 6. Bitwise Operator

• C has a distinction of supporting special operators known as Bitwise operator.
• These operators are used for manipulation of data at the bit level.
• A bitwise operator operates on each bit of data.
• & : Bitwise AND Bitwise OR Bitwise Exclusive Shift Left Shift Right

#### 7. Increment/Decrement Operator

• These operators are used to increment or decrement the value by 1.
• These are the unary operators.
• Syntas: Increment/Decrement_operator Variable_name;
• Ex:
• ++a;
• ++b;
• --a;
• --b;
• The above syntax and example are know as pre-increment or pre-decrement.
• Varibale_name Increment/Decrement_operator;
• Ex:
• a++;
• b++;
• a--:
• b--;
• These are called post-increment or post-decrement.

#### 8. Special Operator

• C Programming Language supports some special operatos like Comma (,), Address (&), Pointer (*), sizeof().
• The comma operator is used to link related expression together. It is evaluated from left to right.
• The address operator is used to display the location value of a variable.
• The pointer operator is used to display the vaulue stored in a given address.
• The sizeof() operator is used to display the size of a datatype.

## CONSTANTS in C Programming • C constants are like normal variables, but the only difference is their value can't be modified by the program once defined.
• Constants have the fixed values.
• The constants are also called as Literals.
• Constants may be belonging to any of the datatypes.
• There are a few types of constants;
1. Numeric Constant.
2. Non-numeric Constant.

## 1. Numeric Constant:

• Numeric constant stands for a number.
• The number can be integer, fraction etc.
• Real numbers are also considered as the numeric constants.
• Real constants are the combination of integer and fraction.

### a. Integer Constant:

• Integers are the natural numbers including zero.
• Integer constants may be decimal, octal, hexadecimal constants.
• Decimal: {0,1,2,3,4,5,6,7,8,9}
• Octal: {0,1,2,3,4,5,6,7,8,9}
• Hexadecimal: {0,1,2,3,4,5,6,7,8,9, A, B,C,D,E,F}
• Integers may be Signed Integer and Unsigned Integer.
• Signed Integer refers to the -ve and +ve values including zero.
• Unsigned Integer refers to the +ve values including zero.
• The largest integer number that can be stored in a 16-bit computer is 215 - 1.
• The largest integer number that can be stored in a 32-bit computer is 231 - 1.
• The Octal constants are written with a leading zero.
• Ex: 0234
• The Hexadecimal constants are written in a leading 0x.
• Ex: 0x49B

#### Rules for Integer Constant:

1. An integer constant must have at least one digit.
2. It must not have a decimal point.
3. It can be either positive or negative.
4. If no sign precedes an integer constant, it is assumed to be positive.
5. Commas or blanks are not allowed within an integer constant.

### b. Floating-Point Constant:

• A fraction is used for scientific notation or exponent form.
• The floating point number has two parts.
• One is a decimal part and another part is a fractional part.
• While representing in fractional form, we have to include the decimal point.
• And sometimes we have to use e or E.
• Ex:
• 3.234
• 3234E3
• Both the examples have the same value but presented in two ways.

## 2. Non-numeric Constant:

• Non-numeric constants are the constants except the number.
• The non-numeric constants may be Character or String constants.

### a. Character Constant:

• Character constants are always written in the single quoted form.
• Ex: 's'
• Character constants can be a single character or an escape sequence or a universal character.
• Plain Character: 'a', 'b', 'x' etc.
• Escape Sequence: '\n', '\t', '\a' etc.
• Universal Character: '\u02C0',

### b. String Constant:

• A collection of characters is known as a string.
• These are written in double-quoted form.
• Always a string constant is terminated with a special character called known as null character.
• Ex: "Welcome"

## Constant Defining:

There are two ways to define CONSTANTS in C Programming-
1. Using const keyword.
2. Using #define preprocessor.

### a. Using const Keyword:

Syntax: const type variablename = value;
Example:

#include<stdio.h>

void main()
{
const int op1 = 10;
const int op2 = 15;
int addition;
addition = op1 + op2;
printf("The addition is = %d", addition);
}

Output: The addition is = 25

### b. Using #define Preprocessor:

Syntax: #define variablename value
• We don't need to put a semicolon (;) for the termination.
Example:

#include<stdio.h>

#define op1 10
#define op2 15

void main()
{
int addition;
addition = op1 + op2;
printf("The addition is = %d", addition);
}

Output: The addition is = 25

## IDENTIFIERS in C Programming • The elements of a program are named with a specific name called as Identifiers.
• Identifiers used to identify the variables, functions, pointers and some user-defined datatypes.
• Identifiers in a program are unique.
• Ex: int mark;
• Here mark is an identifier.
• There are some rules for the Identifiers.

### Rules for Identifiers:

1. The name of an Identifier always starts with an alphabet or underscore ( _ ).
2. It must not be a keyword.
3. There mustn't have any space in between any alphabets.
4. Identifiers are case sensitive.
5. Punctuation and special characters aren’t allowed except underscore.
6. It may be the combination of alphabets and digits, but the 1st letter must be an alphabet.

### Example of Identifiers:

int x;
float percentage;
double simple_interest;
string name1;
string name2
int _number2;
• Here x, percentage, simple_interest, name1 and name2 are the identifiers.
• Identifiers may be a single character, word, combination of word and number.
• The name of identifier must start with alphabet, but we could use _ from the symbols.

## KEYWORDs in C Programming • Keywords are the predefined word by the compiler.
• These are the reserve words having a fixed meaning.
• Each keyword is meant to perform a specific task assigned by the compiler.
• The keywords are only used to perform their task only, they can't be used as any variables.
• All the keywords are written in lower case letter only since C is case sensitive.
• There are 32 Keywords in C Programming.

1. void
2. auto
3. break
4. case
5. char
6. const
7. continue
8. default
9. do
10. double
11. else
12. enum
13. extern
14. float
15. for
16. goto
17. if
18. int
19. long
20. register
21. return
22. short
23. signed
24. sizeof
25. static
26. struct
27. switch
28. typedef
29. union
30. unsigned
31. volatile
32. while

## printf() & scanf() in C Programming • printf() and scanf() functions are inbuilt library functions in C programming language. These are available in C library by default. These functions are included in <stdio.h> library fucntion.
• We have to include the <stdio.h> library function file at the beginning of our C Programming to use the printf() and scanf() function.

### 1. printf() Function in C Programming:

• In C Programming, printf() function is used to print an output to the output window.
• We could print Characters, String, Float, Integer, Octal and Hexadecimal values to the output screen.
• We use printf() function with format specifiers (%d, %c, %s, %f, %x, %lf) to display the value of the diferent datatypes.
• To generate a newline, we have to use "\n" within C printf() statement.
• We have to use "\t" to generate a tab horizontally and "\v" for a vertical line.
N.B.:

• C Programming Language is case sensitive.
• So we have to write the keywords in lower case letter only.

#### Example Program for printf() Function:

#include <stdio.h>
int main()
{
char ch = 'O';
char str = "Odia Guru Online";
float flt = 68.322;
int no = 143;
double dbl = 92.123456;
printf("Character is %c \n", ch);
printf("String is %s \n" , str);
printf("Float value is %f \n", flt);
printf("Integer value is %d\n" , no);
printf("Double value is %lf \n", dbl);
return 0;
}

#### Output:

Character is O
String is Odia Guru Online
Float value is 68.322000
Integer value is 143
Double value is 92.123456

### 2. scanf() Function in C Programming:

• In C Programming, scanf() function is used to get an input from the keyboard.
• We could get Characters, String, Float, Integer, Octal and Hexadecimal values from the keyboard.
• We use scanf() function with format specifiers (%d, %c, %s, %f, %x, %lf) to take the value of the different datatypes from the keyboard.
• We have to use the "&" to assign the inputted value to the variable.

#### Example Program for scanf() Function:

#include <stdio.h>
int main()
{
char ch;
char str;
printf("Enter any character \n");
scanf("%c", &ch);
printf("Entered character is = %c \n", ch);
printf("Enter any string ( up to 50 character ) \n");
scanf("%s", &str);
printf("Entered string is %s \n", str);
}

#### Output:

Enter any character
i
Entered character is i
Enter any string ( up to 50 character )
hello
Entered string is hello