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static boolean isPrime(int n){
boolean result=true;
if(n <= 1) return false;
for(int i = 2; i <= n/2; i++){ //n/2 because the largest factor of any number is either it's half or less than it
if(n % i == 0){
result = false; //if some number divides it, then prime=false;
break;
}
}
return result;
}
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public class PrimeChecker {
public static boolean isPrime(int num) {
if (num <= 1) {
return false;
}
for (int i = 2; i <= Math.sqrt(num); i++) {
if (num % i == 0) {
return false;
}
}
return true;
}
public static void main(String[] args) {
int number = 17; // Replace with the number to be checked
if (isPrime(number)) {
System.out.println(number + " is a prime number.");
} else {
System.out.println(number + " is not a prime number.");
}
}
}
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import java.util.Scanner;
class main {
public static void main(String [] args) {
Scanner kb = new Scanner(System.in);
System.out.print("? ");
int num1 = kb.nextInt();
boolean res = isprime(num1);
System.out.println(res);
}
public static boolean isprime(int num1) {
boolean ans = true;
int i = 1;
for(i = 2;i < num1;i++) {
if((num1 % i == 0) && (num1 != 2)) {
ans = false;
break;
}else{
ans = true;
break;
}
}
return ans;
}
}