3.9 Relational Operators: , , ,

3.9 Relational Operators: < , <= , > , >=

Given that a and b represent numeric expressions, the relational (also called comparison ) operators are defined as shown in Table 3.6.

Table 3.6. Relational Operators

a < b	a less than b ?
a <= b	a less than or equal to b ?
a > b	a greater than b ?
a >= b	a greater than or equal to b ?

All relational operators are binary operators, and their operands are numeric expressions. Binary numeric promotion is applied to the operands of these operators. The evaluation results in a boolean value. Relational operators have precedence lower than arithmetic operators, but higher than that of the assignment operators.

 double  hours = 45.5; boolean overtime = hours >= 35.0;    // true. boolean order = 'A' < 'a';           // true. Binary numeric promotion applied. 

Relational operators are nonassociative. Mathematical expressions like a b c must be written using relational and boolean logical/conditional operators.

 int a = 1, b = 7, c = 10; boolean valid1 = a <= b <= c;             // (1) Illegal. boolean valid2 = a <= b && b <= c;        // (2) OK. 

Since relational operators have left associativity, the evaluation of the expression a <= b <= c at (1) in the examples above would proceed as follows : ((a <= b) <= c) . Evaluation of (a <= b) would yield a boolean value that is not permitted as an operand of a relational operator, that is, ( < boolean value > <= c) would be illegal.