java 获取第n个素数

 

//find n'th prime number

import java.util.Scanner;

public class Numbers {

    public static void main(String[] args) {
        int n, count = 0, i = 2;
        Scanner ip = new Scanner(System.in);
        System.out.print("Enter the value of n: ");
        n = ip.nextInt();
        while (count <= n) {
            if (isPrime(i)) {
                count++;
                if (count == n)
                    System.out.println("The " + n + "th prime number is " + i);
            }
            i++;
        }
        ip.close();
    }

    private static boolean isPrime(int num) {
        for (int i = 2; i <= Math.sqrt(num); i++) {
            if (num % i == 0)
                return false;
        }
        return true;
    }
}



OUTPUT:
Enter the value of n: 5
The 5th prime number is 11