Relational Operator

Relational Operator

      A relational operator is a symbol that is used to compare two values of the same type. The result of the comparison is True (or 1) or False (or 0). The relational operators are used to specify conditions in programs. The relational operators are also known as comparison operators.
      C-language provides six basic relational operators. These operators with symbols, meanings and with examples are given below. The variables 'a' , 'b', and 'c' are used in examples. Suppose, value of 'a' is 10, 'b' is 5 and 'c' is 10.

Operator	Meaning	Purpose	Example
==	Equal to	Return true if both values are equal; otherwise return false.	a == b return false
!=	Not Equal to	Return true if both values are different; otherwise return false.	a! = b return true
>	Greater than	Return true if first value is greater; otherwise return false.	a > b return true
<	Less than	Return true if first value is less than; otherwise return false.	a < b return false
>=	Greater than or Equal to	Return true if first value is greater than or equal to second; otherwise return false.	a >= c return true
<=	Less than or Equal to	Return true if first value is less than or equal to second; otherwise return false.	a <= c return true

Relational Expression

      An expression that contains two operands and one relational operator between these operands is called relational expression. The relational expression returns true (or 1) or false (or 0). The relational expression is used in conditional statement (or looping statements) as test condition. In C, true can be represented by any non-zero value while false can be represented by zero value.
      For example, a > b is a relational expression. It returns true if the value of 'a' is greater than 'b', otherwise it returns false. Suppose a = 6, b = 9 and c = 6. The relational expression and their output values are shown in the following table.

Relational Operator	Output
a > c         a <= c            a < b            a >= c            a == b            a != c	False True True True False False