Showing posts sorted by relevance for query sieve-of-Eratosthenes-algorithm-to-generate-prime-numbers-in-java. Sort by date Show all posts
Showing posts sorted by relevance for query sieve-of-Eratosthenes-algorithm-to-generate-prime-numbers-in-java. Sort by date Show all posts

Sunday, November 24, 2019

Java Plan To Impress Prime Numbers From Ane To 100

In this article, I'll part yous a unproblematic work near writing a Java programme to impress prime numbers upwards to a given publish e.g. tell prime numbers from 1 to 100. It's 1 of the most mutual coding exercises for programmers learning inwards Java, equally it gives yous an chance to acquire to a greater extent than near essential operator inwards Java Programming. The fundamental hither is that yous cannot purpose a library portion which tin shipping away exactly your job, yous involve to devise the algorithm for checking prime publish past times yourself. One of the most pop algorithms for generating prime is Sieve of Eratosthenes,  which nosotros get got discussed earlier, but inwards this post, nosotros volition get got a simpler approach. We'll commencement write a portion to cheque whether a publish is prime or non in addition to thus nosotros loop through commencement 100 numbers i.e. from 1 to 100 in addition to impress entirely those which passed the prime test. Btw, if yous are looking for around serious programming coding inquiry for the interview, thus yous tin shipping away too get got a await at Cracking the coding interview, which contains to a greater extent than than 150 coding inquiry amongst solutions.



How to cheque if a publish is prime or not

H5N1 publish is said to hold upwards prime if it's non divisible past times whatsoever publish other than itself e.g. 2, three or 5. 1 is non counted equally a prime number, thus the lowest prime publish is 2. One of the easiest agency to cheque whether a publish is prime or not is to loop from 2 to the publish itself in addition to checks if it's divisible past times whatsoever publish inwards betwixt or not.

You tin shipping away produce that cheque past times using modulus operator inwards Java, which provide naught if a publish is perfectly divisible past times around other number. If the publish yous are checking is non divisible past times anyone thus it's a prime publish otherwise, it's non a prime number.

But this logic tin shipping away hold upwards farther optimized to entirely loop through the foursquare rootage of the publish instead of the publish itself, equally shown inwards below example. This volition brand the Java programme fast for checking large prime numbers.



Here is a listing of all prime numbers betwixt 1 in addition to 100:
ll part yous a unproblematic work near writing a Java programme to impress prime numbers upwards to a  Java Program to impress prime numbers from 1 to 100


An optimized agency to generate Prime numbers from 1 to 100

/**  * Java Program to impress prime numbers from 1 to 100  *  * @author Javin Paul  */ public class PrimeNumberGenerator {      public static void main(String args[]) {          // impress prime numbers from 1 - 100         System.out.println("Prime numbers from 1 to 100 ");          for (int i = 2; i <= 100; i++) {             if (isPrime(i)) {                 System.out.println(i);             }         }     }      /*      * An optimized to cheque if a publish is prime or not.      */     public static boolean isPrime(int num) {         if (num == 2 || num == 3) {             return true;         }          if (num % 2 == 0 || num % 3 == 0) {             return false;         }          for (int i = 3; i < Math.sqrt(num); i += 2) {             if (num % i == 0 || num % Math.sqrt(num) == 0) {                 return false;             }         }         return true;      } }  Output: Prime numbers from 1 to 100  2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

That's all near how to impress prime numbers inwards Java from 1 to 100.  Let me know if yous uncovering whatsoever põrnikas on this programme or yous intend if this programme volition non operate inwards whatsoever specific scenario. This looks much to a greater extent than optimized than looping till the publish itself.

Here are dyad of to a greater extent than coding problems for practice:
  • Top 10 Programming problems from Java Interviews? (article)
  • Write code to implement Quicksort algorithm inwards Java? (algorithm)
  • How produce yous swap 2 integers without using a temporary variable? (solution)
  • Write a programme to cheque if a publish is a ability of 2 or not? (solution)
  • How to contrary String inwards Java without using StringBuffer? (solution)
  • Write a programme to code insertion kind algorithm inwards Java (program)
  • How to uncovering a missing publish inwards a sorted array? (solution)
  • How to calculate factorial using recursion in addition to iteration? (solution)
  • How produce yous contrary give-and-take of a judgement inwards Java? (solution)
  • How to uncovering duplicate characters from String inwards Java? (solution)
  • How to contrary an int variable inwards Java? (solution)
  • How to cheque if a twelvemonth is a leap twelvemonth inwards Java? (answer)
  • Write code to implement Bubble kind algorithm inwards Java? (code)
  • How to impress Pyramid pattern inwards Java? (solution)
  • How to cheque if a given publish is prime or not? (solution)
  • How to solve FizzBuzz work inwards Java? (solution)
  • Write a programme to impress the highest frequency give-and-take from a text file? (solution)
  • How to withdraw duplicate elements from ArrayList inwards Java? (solution)
  • How to uncovering if given String is a palindrome inwards Java? (solution)

Further Reading
The Coding Interview Bootcamp: Algorithms + Data Structures
Data Structures in addition to Algorithms: Deep Dive Using Java
Algorithms in addition to Data Structures - Part 1 in addition to 2

Saturday, November 9, 2019

Java Plan To Calculate Perimeter/Circumference Of Circle

One of the mutual programming practise for beginners is to write a plan to calculate the perimeter or circumference of a circle inward Java. This practise is non simply mutual inward Java but too on other programming linguistic communication courses e.g. C, C++ or Python. I start did this practise on C++ long ago, but that fourth dimension the joy of a working plan was something different. I was quite happy to run across my plan compiled without mistake as well as tin impress the right circumference after entering radius. That plan taught me how to convey input from a user as well as how to display output into the console, I didn't know how to do methods to encapsulate code. For us, entirely principal method matters at that time. Anyway, let's focus on the chore at manus i.e. how to honor the circumference of Circle of given radius. You receive got to convey radius from the user as well as present the output to console.

In gild to calculate the perimeter of a circle, yous must start retrieve the formula to calculate the circumference of a circle. Well, the formula is non hard to remember, it's  2*PI*R, where PI is well-known Mathematics constant as well as R is the radius of the circle.

You tin acquire the value of PI inward Java past times accessing Math.PI constant. Some programmer similar to set the value of PI every bit 3.14 which is Ok for testing as well as demo, but non expert for anything else. You should job the Math.PI wherever yous postulate the value of PI inward Java program.





Java Program to calculate Circumference of circle

Now nosotros postulate a value of radius which tin live on a user-provided value, alternatively, yous tin too overstep inward the plan itself.

Let run across the start selection if nosotros become past times user value our plan volition prompt the user to locomote inward a value for the radius. The Scanner course of pedagogy is used to convey user input from the console it has many utility methods to acquire information from console later on volition convert user input to the desired shape as well as thence overstep the radius to perimeter() function to calculate the circumference of the circle as well as shop the effect as well as valid variable.

straight off if nosotros become the minute selection it's really uncomplicated inward the plan itself nosotros tin overstep the value of radius as well as thence job that value to calculate the perimeter of the circle as well as thence display the result.

Here is our consummate Java plan to accept input from the user as well as impress output into the console. We receive got used perimeter() role to calculate the circumference of the circle. This method returns a double value because PI is a floating signal constant.


mport java.util.Scanner;  /* * Java Program to calculate circumference of circle */ public class Main {  public static void main(String args[]) {  //creating scanner to convey radius of circle Scanner scanner = new Scanner(System.in); System.out.println("Welcome inward Java plan to calculate Perimeter of circle"); System.out.println("Formula for calculating perimeter of circle is '2*PI*R' ");  System.out.println("Please locomote inward radius of circle:"); float radius = scanner.nextFloat();   double perimeter = perimeter(radius);  System.out.println("Perimeter of Circle calculate past times Java plan is : "  + perimeter);  scanner.close(); }  /* * @return perimeter of a circle.  */ public static double perimeter(float radius){ return 2*Math.PI*radius;  } } 

You tin run this plan past times copying the code into your favorite editor e.g. NotePad++ or IDE similar Eclipse. You tin too run it from the ascendence job if yous are non familiar amongst whatever IDE. In gild to run from the ascendence line, yous too postulate to compile the course of pedagogy using javac command. This volition create the course of pedagogy file which yous tin run using coffee ascendence every bit shown below:

$javac Main.java $java Main

Remember, when nosotros compile nosotros supply the advert of source file but when nosotros run nosotros supply the advert of the course of pedagogy which contains main() method, This is the fundamental divergence betwixt compiling as well as running a Java program. When yous run, the plan volition create next output:

Welcome inward Java plan to calculate Perimeter of circle Formula for calculating perimeter of circle is '2*PI*R'  Please locomote inward radius of circle: 4 Perimeter of Circle calculate past times Java plan is : 25.132741228718345

You tin run across that user entered value of radius every bit iv as well as plan printed out the circumference of the circle every bit 25.13, which is right every bit per next formula:

 One of the mutual programming practise for beginners is to write a plan to calculate t Java Program to calculate Perimeter/Circumference of Circle


That's all nigh how to calculate the circumference or perimeter of the circle inward Java. It's i of the uncomplicated Java programming exercises but actually assistance yous construct your coding skill. You acquire as well as empathize how to job basic operators, API, as well as functions to solve roughly mutual mathematics problems. I strongly recommend Java beginners to solve every bit many problems every bit possible.

Further Learning
The Coding Interview Bootcamp: Algorithms + Data Structures
Data Structures as well as Algorithms: Deep Dive Using Java
solution)
  • How to transpose a matrix inward Java? (solution)
  • How to implement binary search using recursion inward Java? (solution)
  • How to opposite a String inward house inward Java? (solution)
  • Java Program to impress Prime numbers from 1 to 100? (program)
  • How to implement Linear Search inward Java? (solution)
  • How to honor largest prime factors of a given integer inward Java? (program)
  • How to opposite words inward a given String inward Java? (solution)
  • How to honor all prime factors of a divulge inward Java? (solution)
  • How to depository fiscal establishment fit if 2 given Strings are Anagram inward Java? (solution)
  • How to generate prime numbers upward to 100 using Sieve of Eratosthenes Algorithm(program)
  • How to remove duplicate characters from String inward Java? (solution)
  • How to depository fiscal establishment fit if a yr is a saltation yr inward Java? (solution)
  • How to honor the foursquare rootage of a divulge without using a library role inward Java? (program)
  • How to remove duplicate elements from the array inward Java? (solution)
  • How to depository fiscal establishment fit if given divulge is prime inward Java (solution)
  • How to depository fiscal establishment fit if a divulge is binary inward Java? (algorithm)
  • How to calculate Area of Triangle inward Java? (program)
  • How to impress Fibonacci serial inward Java (solution)
  • How to calculate the foursquare rootage of a given divulge inward Java? (solution)
  • How to honor the highest occurring give-and-take from a given file in Java? (solution)
  • How to depository fiscal establishment fit if given String is palindrome or non inward Java? (solution)
  • How to depository fiscal establishment fit if 2 rectangles intersect amongst each other inward Java? (solution)
  • How to honor all permutations of a given String inward Java? (solution)
  • How to depository fiscal establishment fit if a String contains duplicate characters inward Java? (solution)
  • How to calculate the amount of all elements of an array inward Java? (program)
  • How to opposite an array inward house inward Java? (solution)
  • How to impress prime divulge upward to a given divulge inward Java? (solution)
  • How to honor if given Integer is Palindrome inward Java? (solution)
  • How to calculate the average of all numbers of an array inward Java? (program)

  • Thanks for reading this article thence far, if yous similar this article thence delight portion amongst your friends as well as colleagues. If yous receive got whatever questions or feedback thence delight driblet a comment.  If yous receive got simply started learning Java as well as looking for a expert mass every bit a companion, I advise yous purchase Head First Java, 2d Edition, i of the best books to acquire center Java from scratch.