Q.Write a Java program to take a number from the user and check whether it is prime or not. If it is prime then predict the next 3 primes or find the nearest prime?
package simplepro;
import java.util.Scanner;
public class PrimeValid{
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
System.out.print("Enter the Number: ");
int n=in.nextInt();
if(n>1) {
boolean isPrime=primeCheck(n);
int limit=n+100;
byte count =0;
if(isPrime) {
System.out.println(n +" is Prime Number :");
for(int i=n+1,j=1;i<limit;i++) {
boolean checkPrime=primeCheck(i);
if(checkPrime) {
System.out.println("Next "+ j+" Prime Number: "+i);
count++;
j++;
if(count>=3) {
break;
}
}
}
}
else {
while(n>2) {
n++;
if(primeCheck(n)) {
System.out.println(n+" is not Prime Number !!");
System.out.println("Nearest Prime Number : "+n);
break;
}
}
}
}
else {
System.out.println("Please Enter above 1 numbers only");
}
}
public static boolean primeCheck(int n) {
int count=0;
for(int j=2 ; j<n; j++){
if(n%j==0)
count++;
}
if(count==0)
return true;
else
return false;
}
}
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