Java Math Operators and special operators

- Addition.
- Subtraction.
- Multiplication
- Division
- Remainder
- Special operators
Addition
We perform addition by using +
operator on numeric data types
int num1 = 5;
int num2 = 6;
int sum = num1 + num2;
System.out.println(sum); // 11int num3 = sum + 10;
System.out.println(num3); // 21num3 = num3 + 1;
System.out.println(num3); // 22
Subtraction
We perform addition by using —
operator on numeric data types
int num1 = 5;
int num2 = 6;
int sum = num2 - num1;
System.out.println(sum); // 1int num3 = 100 - sum;
System.out.println(num3); // 99num3 = num3 - 10;
System.out.println(num3); // 89
Multiplication
We perform multiplication by using *
operator on numeric data types
int num1 = 5;
int num2 = 6;
int sum = num1 * num2;
System.out.println(sum); // 30sum = sum * 2;
System.out.println(sum); // 60
Division
We perform division by using /
operator on numeric data types
int num1 = 50;
int num2 = 10;
int sum = num1 / num2;
System.out.println(sum); // 5// Sometimes when dividing we can get a floating numberint num3 = 5 / 2;
System.out.println(num3); // 2
// Actual result is 2.5 but we should always remember that int is only for whole numbers so it will be 2.int num4 = 8 / 5;
double num5 = 8.0 / 5;
System.out.println(num4); // 1
System.out.println(num5); // 1.6
// remember it will not round, it will always truncate
Remainder
The remainder operator will calculate what remains after division. %
— this is the remainder.
System.out.println(12 % 10); // 2 because 12 / 10 is 1 and 2 remains
System.out.println(12 % 5); // 2 because 12 / 5 is 2and 2 remains
System.out.println(10 % 5); // 0
System.out.println(107 % 10); // 7
System.out.println(9 % 4); // 1
System.out.println(119 % 100); // 19
System.out.println(25 % 10); // 5
System.out.println(12 % 3); // 0
Special operators
Regular:
int i = 5;
i = i + 2;
System.out.println(i); // 7
With special operator:
int i = 5;
i += 2;
System.out.println(i); // 7
Both above examples are doing the exact same thing — adding 2 to our i variable.
Regular:
int i2 = 10;
i2 = i2 - 2;
System.out.println(i2); // 8int i3 = 4;
i3 = i3 * 3;
System.out.println(i3); // 12int i4 = 10;
i4 = i4 / 2;
System.out.println(i4); // 5
With special operator:
int i2 = 10;
i2 -= 2;
System.out.println(i2); // 8int i3 = 4;
i3 *= 3;
System.out.println(i3); // 12int i4 = 10;
i4 /= 2;
System.out.println(i4); // 5
Increment and Decrement operators
The increment operator will increase the value of a numeric variable by 1.
int num = 10;
num++;
System.out.println(num); // 11System.out.println(num++); // 11
System.out.println(num); // 12System.out.println(++num); // 13
- post-increment (++ after variable) will increase value in the next statement.
- pre-increment will increase value immediately.
The decrement operator will decrease the value of a numeric variable by 1.
int num = 10;
num--;
System.out.println(num); // 9System.out.println(num--); // 9
System.out.println(num); // 8System.out.println(--num); // 7
- post-decrement(after variable) will decrease value in the next statement.
- pre-decrement will decrease value immediately.
This article is part of the series of articles to learn Java programming language from Tech Lead Academy.
1. Introduction to programming
2. OS, File, and File System
3. Working with terminal
4. Welcome to Java Programming Language
5. Variables and Primitives in Java
6. Methods with Java
7. Java Math Operators and special operators
8. Conditional branching, comparision and logical operators
9. Switch statemet and ternary operator
10. Enum
11. String and its methods in Java
12. Loops in Java
13. Class, Object and constructor in Java
14. Object Oriented Programming in Java
15. Encapsulation in Java
16. Inheritance in Java
17. Abstraction in Java
18. Polymorphism in Java
19. Overriding vs Overloading in Java
20. OOP Design Principles in Java
21. Array in Java
22. Data Structures with Java
23. Collection framework in Java
24. ArrayList in Java
25. Set in Java
26. Map in Java
27. LocalDate in Java
28. Exception in Java
29. IO in Java
30. Design Patterns
31. JUnit