Operators in C by G Krishna Chauhan

An operator is a symbol that tells the compiler to perform specific mathematical or logical functions. C language is rich in built-in operators and provides the following types of operators −

• Arithmetic Operators
• Increment and Decrement Operators
• Assignment Operators
• Relational Operators
• Logical Operators
• Conditional Operators
• Bitwise Operators
• Special Operators
• C Arithmetic Operators:
  An arithmetic operator performs mathematical operations such as addition, subtraction and multiplication on numerical values (constants and variables).
  
  
  
  
• Increment and decrement operators:C programming has two operators increment ++ and decrement -- to change the value of an operand (constant or variable) by 1.
  Increment ++ increases the value by 1 whereas decrement -- decreases the value by 1. These two operators are unary operators, meaning they only operate on a single operand.
  #include <stdio.h>

Example Program:

#include <stdio.h>

int main()

{

    int a = 10, b = 100;

    float c = 10.5, d = 100.5;

    printf("++a = %d \n", ++a);

    printf("--b = %d \n", --b);

    printf("++c = %f \n", ++c);

    printf("--d = %f \n", --d);

    return 0;

}

Output:

++a = 11

--b = 99

++c = 11.500000

++d = 99.500000

• C Assignment Operators:

An assignment operator is used for assigning a value to a variable. The most common assignment operator is =

Example Program:

#include <stdio.h>

int main()

{

    int a = 9,b = 4, c;    

    c = a+b;

    printf("a+b = %d \n",c);

    c = a-b;

    printf("a-b = %d \n",c); 

    c = a*b;

    printf("a*b = %d \n",c); 

    c=a/b;

    printf("a/b = %d \n",c);    

    c=a%b;

    printf("Remainder when a divided by b = %d \n",c);

    return 0;

}

Output:

a+b = 13

a-b = 5

a*b = 36

a/b = 2

Remainder when a divided by b=1

• C Relational Operators:

A relational operator checks the relationship between two operands. If the relation is true, it returns 1; if the relation is false, it returns value 0.

Relational operators are used in decision making and loops.

Example Program:

#include<stdio.h>

int main()

{

    int a = 5, b = 5, c = 10;

    printf("%d == %d = %d \n", a, b, a == b); // true

    printf("%d == %d = %d \n", a, c, a == c); // false

    printf("%d > %d = %d \n", a, b, a > b); //false

    printf("%d > %d = %d \n", a, c, a > c); //false

    printf("%d < %d = %d \n", a, b, a < b); //false

    printf("%d < %d = %d \n", a, c, a < c); //true

    printf("%d != %d = %d \n", a, b, a != b); //false

    printf("%d != %d = %d \n", a, c, a != c); //true

    printf("%d >= %d = %d \n", a, b, a >= b); //true

    printf("%d >= %d = %d \n", a, c, a >= c); //false

    printf("%d <= %d = %d \n", a, b, a <= b); //true

    printf("%d <= %d = %d \n", a, c, a <= c); //true

    return 0;

}

Output

5 == 5 = 1

5 == 10 = 0

5 > 5 = 0

5 > 10 = 0

5 < 5 = 0

5 < 10 = 1

5 != 5 = 0

5 != 10 = 1

5 >= 5 = 1

5 >= 10 = 0

5 <= 5 = 1

5 <= 10 = 1 

• C Logical Operators:

An expression containing logical operator returns either 0 or 1 depending upon whether expression results true or false. Logical operators are commonly used in decision making in C programming.

Example Program:

#include <stdio.h>

int main()

{

    int a = 5, b = 5, c = 10, result;

    result = (a = b) && (c > b);

    printf("(a = b) && (c > b) equals to %d \n", result);

    result = (a = b) && (c < b);

    printf("(a = b) && (c < b) equals to %d \n", result);

    result = (a = b) || (c < b);

    printf("(a = b) || (c < b) equals to %d \n", result);

    result = (a != b) || (c < b);

    printf("(a != b) || (c < b) equals to %d \n", result);

    result = !(a != b);

    printf("!(a == b) equals to %d \n", result);

    result = !(a == b);

    printf("!(a == b) equals to %d \n", result);

    return 0;

}

Output:

(a = b) && (c > b) equals to 1 

(a = b) && (c < b) equals to 0 

(a = b) || (c < b) equals to 1 

(a != b) || (c < b) equals to 0 

!(a != b) equals to 1 

!(a == b) equals to 0 

• Bitwise Operators

During computation, mathematical operations like: addition, subtraction, addition and division are converted to bit-level which makes processing faster and saves power.

Bitwise operators are used in C programming to perform bit-level operations.