Programs That Calculate

Arithmetic Expressions +addition -subtruction *multiplication /division  Order of Operations BEDMAS (brackets, exponentiation, division, multiplication, addition, subtraction)

Evaluate the expression: (5-8/2)*3+5  Java proceeds as follows: => (5-4)*3+5 => (1)*3+5 => 3+5 => 8

 Operations on values of the same type produce values of that type Example: 15/3=> 9/5 => 5 1 Note that when we divide 2 integers, the result is the integral quotient with any remainder being ignored!

Division by ZERO  In Math, division by zero is undefined  In Java, if we divide a number by ZERO, Java throws an arithmetic exception  If any exception is thrown during the execcution of a program, the programmer can write instructions to catch the exception I can’t cope with this!!!!

modulo  Useful Arithmetic operator written as %  Has same precedence as multiplication and divison  % gives the remainder Example 7%3 => 8%0 => 20%7 => 6 Throws an Arithmetic Exception 1

public class ArithmeticProg {public static void main(String[] args) { int i = 10, j = 20; System.out.println("Adding"); System.out.println(" i + j = " + (i + j)); System.out.println("Subtracting"); System.out.println(" i - j = " + (i - j)); System.out.println("Multiplying"); System.out.println(" i * j = " + (i * j)); System.out.println("Dividing"); System.out.println(" i / j = " + (i / j)); System.out.println("Modulus"); System.out.println(" i % j = " + (i % j)); }// main //ArithmeticProg class

Increment and Decrement Operators ++ operator adds one to the current value of an int or char. -- operator subtracts one to the current value of an int or char.  Neither operator works on doubles, booleans or Strings Example: n++; and ++n; are equivalent to n = n+1; n--; and --n; are equivalent to n = n-1; char c = ‘A’ c++; //will change the value c to ‘B’

Assignment Operators + = is equivalent to: = + Example x+= 3 is equivalent to x=x+ 3 x +=Y-2 is equivalent to x=x+(Y-2)

Assignment can also be combined with the other four basic arithmetic operators: -=*= /=%=  Example: x -=Y+3 is equivalent to x=x-(Y+3) n *= 5 is equivalent to n=n*5

Multiple assignments in one statement:  Operators are applied from right to left Example: i=j=k=1 is equivalent to i=(j=(k=1))

Using Math Methods  Math.abs(-4) => 4  Math.sqrt(25) => 5  Math.pow(2, 10) => 1024  Math.max(10, 2) => 10  Math.min(10, 2) => 2