Operators in C Language

An operator is a symbol that performs an operation on a value or variable. In this tutorial, we will learn about various C operators like arithmetic, increment, assignment, relational, logical and bitwise, with the help of examples.

An operator is a symbol which indicates compiler to perform a specific mathematical or logical operation on some values. C language is rich in built-in operators and provides the following types of operators:

1. C Arithmetic Operators:

Arithmetic operators are commonly used to perform various mathematical operations between two values. Below table indicates the arithmatic operators available in C Language:

Example 1: Arithmetic Operators

//Options with the help of arithmatic operators
#include <stdio.h>
int main()
{
    int num1 = 9,num2 = 4, num3;

    num3 = num1+num2;
    printf("num1 + num2 = %d \n",num3);
    num3 = num1-num2;
    printf("num1 - num2 = %d \n",num3);
    num3 = num1*num2;
    printf("num1 * num2 = %d \n",num3);
    num3 = num1/num2;
    printf("num1 / num2 = %d \n",num3);
    num3 = num1%num2;
    printf("Remainder when num1 divided by num2 = %d \n",num3);

    return 0;
}

num1 + num2 = 13
num1 - num2 = 5
num1 * num2 = 36
num1 / num2 = 2
Remainder when num1 divided by num2 = 1

As you might have predicted, the operators +, -, and * compute addition, subtraction, and multiplication, respectively. In basic math, 9/4 = 2.25. However, the output of the program is 2.

It is because num1 and num2 are both integer variables. The output is therefore also an integer. The compiler displays result 2 rather than 2.25 because it ignores the terms after the decimal point.

The remainder is calculated using the modulo operator %. The remainder is 1 when num1 = 9 is divided by num2 = 4. Only integers can be used with the % operator.

2. Increment and Decrement Operators in C:

(i). Increment Operator

The increment operator is used to increase the value of a variable. The value is first increased and then used inside the expression in the Pre-Increment. In the Post-Increment, the value is first used within the expression before being increased.

Syntax:

// PREFIX
++num

// POSTFIX
num++

where num is a variable

Example 2: Increment Operator

#include<stdio.h>
int main()
{
int x =  10 ;
int a ;

x = ++x ;
printf("Value of x = %d \n", x);

a = x++ ;
printf("Value of a = %d \n", a);

printf("New Value of x = %d", a);

return 0;
}

Value of x = 11
Value of a = 11
New Value of x = 11

(ii). Decrement Operator

To decrease the value of a variable in an expression, use the decrement operator. The value is decremented first in the Pre-Decrement and then used inside the expression. In the Post-Decrement, the value is first used within the expression before being decremented.

Syntax:

// PREFIX
--num

// POSTFIX
num--

where num is a variable

Example 3: Decrement Operator

#include<stdio.h>
int main()
{
int x =  10 ;
int a ;

x = --x ;
printf("Value of x = %d \n", x);

a = x-- ;
printf("Value of a = %d \n", a);

printf("New Value of x = %d", a);

return 0;
}

Value of x = 9
Value of a = 9
New Value of x = 9

3. Assignment Operators in C:

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

Example 4: Assignment Operators

#include <stdio.h>
int main()
{
    int num1 = 5, c;

    c = num1;      // c is 5
    printf("c = %d\n", c);
    c += num1;     // c is 10
    printf("c = %d\n", c);
    c -= num1;     // c is 5
    printf("c = %d\n", c);
    c *= num1;     // c is 25
    printf("c = %d\n", c);
    c /= num1;     // c is 5
    printf("c = %d\n", c);
    c %= num1;     // c = 0
    printf("c = %d\n", c);

    return 0;
}

c = 5
c = 10
c = 5
c = 25
c = 5
c = 0

4. Relational Operators in C:

The relationship between two operands is checked by a relational operator. It returns 1 if the relation is true and 0 if the relation is false.

Example 5: Relational Operators

#include <stdio.h>
int main()
{
    int a = 10, b = 10, c = 20;

    printf("%d == %d is %d \n", a, b, a == b);
    printf("%d == %d is %d \n", a, c, a == c);
    printf("%d > %d is %d \n", a, b, a > b);
    printf("%d > %d is %d \n", a, c, a > c);
    printf("%d < %d is %d \n", a, b, a < b);
    printf("%d < %d is %d \n", a, c, a < c);
    printf("%d != %d is %d \n", a, b, a != b);
    printf("%d != %d is %d \n", a, c, a != c);
    printf("%d >= %d is %d \n", a, b, a >= b);
    printf("%d >= %d is %d \n", a, c, a >= c);
    printf("%d <= %d is %d \n", a, b, a <= b);
    printf("%d <= %d is %d \n", a, c, a <= c);

    return 0;
}

10 == 10 is 1
10 == 20 is 0
10 > 10 is 0
10 > 20 is 0
10 < 10 is 0
10 < 20 is 1
10 != 10 is 0
10 != 20 is 1
10 >= 10 is 1
10 >= 20 is 0
10 <= 10 is 1
10 <= 20 is 1

5. Logical Operators in C:

A logical operator expression returns either 0 or 1, depending on whether the expression is true or false. In C programming, logical operators are frequently used in decision making.

| Operator | Name | Example | | -------- | ----------- | ------------------------------------------------------- | --- | ------------------- | | && | Logical And | c=10 && d =2,expression ((c==10) && (d>5)) equals to 0. | | || | Logical Or | If c = 7 and d = 1 then, expression ((c==7) | | (d>5)) equals to 1. | | ! | Logical Not | If x = 5 then, expression !(x==5) equals to 0. |

Example 6: Logical Operators

#include <stdio.h>

int main() {
  int m = 40, n = 20;
  int o = 20, p = 30;
  if (m > n && m != 0) {
    printf("&& Operator : Both conditions are true\n");
  }
  if (o > p || p != 20) {
    printf("|| Operator : Only one condition is true\n");
  }
  if (!(m > n && m != 0)) {
    printf("! Operator : Both conditions are true\n");
  } else {
    printf("! Operator : Both conditions are true. "        "But, status is inverted as false\n");
  }
}

&& Operator: Both conditions are true
|| Operator: Only one condition is true
! Operator: Both conditions are true.But, status is inverted as false

6. Bitwise Operators in C:

Mathematical operations like as addition, subtraction, multiplication, and division are converted to bit-level during computing, which speeds up processing and saves power.