public static void main(String[] args) {
        int sum = 0;
        for (int i = 1; i <=100; i++) {
             if(i%9 != 0 ){
                sum+=i;
            }
        }
        System.out.println("sum = " + sum);
    }

public static void main(String[] args) {
        int sum = IntStream.range(1, 100).filter(i -> (i%9!=0)).sum();
        System.out.println("sum = " + sum);
}