Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Different Methods to find Prime Number in Java
A prime number is a number that is only divisible by one or itself. Some of the prime numbers are 2, 3, 5, 7, 11, 13 etc.
Some of the different methods to find a prime number in Java are given as follows −
Method 1 - Find if a number is prime without using a function
A program that finds if the given number is prime without using a function is given as follow −
Example
public class Example {
public static void main(String args[]) {
int num = 11, flag=0;
if(num == 0||num == 1) {
System.out.println( num + " is not a prime number");
} else {
for(int i = 2; i <= num/2; i++) {
if(num % i == 0) {
System.out.println( num + " is not prime number");
flag = 1;
break;
}
}
if(flag == 0) {
System.out.println( num + " is a prime number");
}
}
}
}Output
11 is a prime number
Method 2 - Find if a number is prime using a function
A program that finds if the given number is prime using a function is given as follow −
Example
public class Example {
static int PrimeOrNot(int num) {
int flag = 0;
if(num == 0||num == 1) {
flag = 1;
} else {
for(int i = 2; i <= num/2; i++) {
if(num % i == 0) {
flag = 1;
break;
}
}
}
return flag;
}
public static void main(String args[]) {
int flag, num = 11;
flag = PrimeOrNot(num);
if(flag == 0) {
System.out.println( num + " is a prime number");
} else {
System.out.println( num + " is not a prime number");
}
}
}Output
11 is a prime number
Updated on: 26-Jun-2020
2K+ Views
Advertisements