public class HelloWorld {
??? public static void main(String[] args)
??? {
??????? int sum = 0;
??????? int num = 0;
??????? do{
???????????
??????????? sum=nmu+sum;
??????????? num+2;
??????? }
??????? while(num<50);
??????? System.out.println("五十以內偶數的和為："+sum);
??? }
}