Numărul prim în Java: număr prim este un număr care este mai mare decât 1 și împărțit doar la 1 sau la el însuși. Cu alte cuvinte, numerele prime nu pot fi împărțite la alte numere decât el însuși sau 1. De exemplu 2, 3, 5, 7, 11, 13, 17.... sunt numere prime.
Notă: 0 și 1 nu sunt numere prime. 2 este singurul număr prim par, deoarece toate celelalte numere pare pot fi împărțite la 2.
Să vedem programul numere prime în java. În acest program java, vom lua o variabilă numerică și vom verifica dacă numărul este prim sau nu.
public class PrimeExample{ public static void main(String args[]){ int i,m=0,flag=0; int n=3;//it is the number to be checked m=n/2; if(n==0||n==1){ System.out.println(n+' is not prime number'); }else{ for(i=2;i<=m;i++){ if(n%i="=0){" system.out.println(n+' is not prime number'); flag="1;" break; } if(flag="=0)" { end of else < pre> <span> Test it Now </span> <p>Output:</p> <pre> 3 is prime number </pre> <h2>Prime Number Program using Method in Java</h2> <pre> public class PrimeExample2{ static void checkPrime(int n){ int i,m=0,flag=0; m=n/2; if(n==0||n==1){ System.out.println(n+' is not prime number'); }else{ for(i=2;i<=m;i++){ if(n%i="=0){" system.out.println(n+' is not prime number'); flag="1;" break; } if(flag="=0)" { end of else public static void main(string args[]){ checkprime(1); checkprime(3); checkprime(17); checkprime(20); < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 is not prime number 3 is prime number 17 is prime number 20 is not prime number </pre> <h2>Prime Number Program in Java (Another way)</h2> <p>You can also use a method where number is not predefined. Here, user has to put the number to check if the number is prime.</p> <pre> import java.util.Scanner; import java.util.Scanner; public class PrimeExample3 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter a number : '); int n = s.nextInt(); if (isPrime(n)) { System.out.println(n + ' is a prime number'); } else { System.out.println(n + ' is not a prime number'); } } public static boolean isPrime(int n) { if (n <= 1) { return false; } for (int i="2;" < math.sqrt(n); i++) if (n % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample1</strong> <h2>Find prime numbers between two numbers</h2> <p>You can also find prime numbers between two specified numbers.</p> <pre> import java.util.Scanner; public class PrimeExample4 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter the first number : '); int start = s.nextInt(); System.out.print('Enter the second number : '); int end = s.nextInt(); System.out.println('List of prime numbers between ' + start + ' and ' + end); for (int i = start; i <= end; i++) { if (isprime(i)) system.out.println(i); } public static boolean isprime(int n) (n <="1)" return false; for (int i="2;" % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample2</strong> </=></pre></=></pre></=m;i++){></pre></=m;i++){> Programul Număr Prim folosind metoda în Java
public class PrimeExample2{ static void checkPrime(int n){ int i,m=0,flag=0; m=n/2; if(n==0||n==1){ System.out.println(n+' is not prime number'); }else{ for(i=2;i<=m;i++){ if(n%i="=0){" system.out.println(n+\' is not prime number\'); flag="1;" break; } if(flag="=0)" { end of else public static void main(string args[]){ checkprime(1); checkprime(3); checkprime(17); checkprime(20); < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 is not prime number 3 is prime number 17 is prime number 20 is not prime number </pre> <h2>Prime Number Program in Java (Another way)</h2> <p>You can also use a method where number is not predefined. Here, user has to put the number to check if the number is prime.</p> <pre> import java.util.Scanner; import java.util.Scanner; public class PrimeExample3 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter a number : '); int n = s.nextInt(); if (isPrime(n)) { System.out.println(n + ' is a prime number'); } else { System.out.println(n + ' is not a prime number'); } } public static boolean isPrime(int n) { if (n <= 1) { return false; } for (int i="2;" < math.sqrt(n); i++) if (n % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample1</strong> <h2>Find prime numbers between two numbers</h2> <p>You can also find prime numbers between two specified numbers.</p> <pre> import java.util.Scanner; public class PrimeExample4 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter the first number : '); int start = s.nextInt(); System.out.print('Enter the second number : '); int end = s.nextInt(); System.out.println('List of prime numbers between ' + start + ' and ' + end); for (int i = start; i <= end; i++) { if (isprime(i)) system.out.println(i); } public static boolean isprime(int n) (n <="1)" return false; for (int i="2;" % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample2</strong> </=></pre></=></pre></=m;i++){> Programul pentru numărul prim în Java (în altă modalitate)
De asemenea, puteți utiliza o metodă în care numărul nu este predefinit. Aici, utilizatorul trebuie să pună numărul pentru a verifica dacă numărul este prim.
import java.util.Scanner; import java.util.Scanner; public class PrimeExample3 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter a number : '); int n = s.nextInt(); if (isPrime(n)) { System.out.println(n + ' is a prime number'); } else { System.out.println(n + ' is not a prime number'); } } public static boolean isPrime(int n) { if (n <= 1) { return false; } for (int i="2;" < math.sqrt(n); i++) if (n % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample1</strong> <h2>Find prime numbers between two numbers</h2> <p>You can also find prime numbers between two specified numbers.</p> <pre> import java.util.Scanner; public class PrimeExample4 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print('Enter the first number : '); int start = s.nextInt(); System.out.print('Enter the second number : '); int end = s.nextInt(); System.out.println('List of prime numbers between ' + start + ' and ' + end); for (int i = start; i <= end; i++) { if (isprime(i)) system.out.println(i); } public static boolean isprime(int n) (n <="1)" return false; for (int i="2;" % 0) true; pre> <p>Output:</p> <strong>Use image PrimeExample2</strong> </=></pre></=>