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public class NguyenToDemo {

    /**

     * main

     *

     * @author viettuts.vn

     * @param args

     */

    public static void main(String[] args) {

        System.out.println("Các số nguyên tố nhỏ hơn 100 là: ");

        for (int i = 0; i < 100; i++) {

            if (isPrimeNumber(i)) {

                System.out.print(i + " ");

            }

        }

    }

    /**

     * check so nguyen to

     *

     * @author viettuts.vn

     * @param n: so nguyen duong

     * @return true la so nguyen so,

     *         false khong la so nguyen to

     */

    public static boolean isPrimeNumber(int n) {

        // so nguyen n < 2 khong phai la so nguyen to

        if (n < 2) {

            return false;

        }

        // check so nguyen to khi n >= 2

        int squareRoot = (int) Math.sqrt(n);

        for (int i = 2; i <= squareRoot; i++) {

            if (n % i == 0) {

                return false;

            }

        }

        return true;

    }

}