Expressions using Operators

Expressions using Operators

AU: May-19, Dec.-19, Marks 13

For handling the expressions the operators are used. C support following set of operators -

Conditional operator :

The conditional operator is? The syntax of using conditional operator is

For example A

a > b?true:false

This means if a is greater than b, if yes then the value will be true otherwise it will be false.

Precedence of Operators

Precedence means the priority of certain operation.

1. In case there is a tie between operations of same priority preference is given to the operator which occurs first.

2. Within a paranthesis, the same hierarchy is operative. If there are more than one set of paranthesis inner most parantheses will be performed first, followed by operations within second.

e.g. a = 3/2*4+3/8+3

Stepwise evaluation to

a = 3/3*4+3/8+3  operation /

= 1*4+3/8+3  operation

= 4+3/8+30  operation

= 4+0+3  operation +

= 4+3 operation +

= 7

Ex. 1.5.1 Determine the output of the following "C" statements: Assume a = 13, b = 25 and c = 5.

i) z = a Λ b ii) x = ++ab iii) y = b++ + C

iv) x = c > b ?1 : 0,

Sol. : i) z = 20 as it is logical bit wise EX-OR operation

The truth table for EX-OR operation is as shown below

As ++a is a pre increment operator the value of a is incremented by one before the expression gets evaluated.

iii) 30 since y = b++c = 25+ 5

As b++ is a post increment operator, after expression gets incremented the value of b becomes 26.

iv) 0

The meaning of this expression is if c> b is true then print 1 otherwise 0. As value of c is less than b the output will be 0.

Review Questions

1. List all the operators in C with an example for each. AU: May-19, Marks 7 oals neo insmeisje

2. Describe the various operators in C with examples and the associativity. AU: Dec.-19, Marks 13