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Similarly, in an expression “a%b*c”, the operators % and * are given without any parenthesis and the modulus will be
executed before the multiplication.
The associativity of some operators is as shown below.

Hierarchy Order Operators Associativity of the Operators
1 postfix unary Right to Left
2 unary including prefix, logical NOT Right to Left
3 multiplication, division and modulus Left to Right
4 addition and subtraction Left to Right

Some Solved Examples:
If int a=5, b=6, c=7, d;
1. d = a%b/c*b;
= 5%6/7*6
= 5/7*6
= 0*6
= 0
2. d = a+b-c+a;
= 5+6-7+5
= 11-7+5
= 4+5
= 9

7.6 ARITHMETICAL EXPRESSION AND STATEMENT
While doing calculations in Java, we come across the term Java expression. Before understanding what it is and how it
differs from a mathematical expression, we must understand the difference between an arithmetical expression and
an arithmetical statement.
Let us see an example:
c = a+b;

Here, a + b is said to be an arithmetic expression and c = a + b; is called an arithmetic statement.

Arithmetic Expression Arithmetic Statement
Any meaningful statement containing identifiers, When an arithmetical expression is assigned to a
literals and arithmetical operators which can produce variable, then it is called an arithmetical statement.
a result is called an arithmetical expression.
Examples: a * b, 2 * (l + b) Examples: c = a * b, p = 2 * (l + b)

7.6.1 Interconversion of Mathematical Expression and Java Expression
We are already familiar with the fact that we cannot write a mathematical expression in a Java program. We must
follow certain rules and convert a mathematical expression into a Java expression. The following table demonstrates
some examples of mathematical expressions and their equivalent Java expressions:

Mathematical Expression Java Expression
pr 2 22.0/7.0 * r * r
2
3x + 2y 3 * x * x + 2 * y
prt
100 (p * r * t) / 100.0

ut+1/2at 2 (u * t) + (1.0 / 2.0 * a * t * t)

Variables and Expressions 169