求大神指点下这个算法结果为啥不对？结果为62

源自：4-8 Java循环语句之 do...while

求大神指点下这个算法结果为啥不对？结果为62

public class dp {

public static void main(String[] args){

int num = 2;

do {

//实现累加求和

num+=num;

num = num + 2;

} while (num<=50);

System.out.println(" 50以内的偶数之和为：" + num );

}

}

提问者：初心noc 2015-08-22 00:18

个回答

天润

2016-01-28 15:28:20

public static void main(String[] args) {
int num = 2;
int sum=0;

do {
//实现累加求和
sum+=num;//sum=sum+num
num = num + 2;
} while (num<=50);
System.out.println(" 50以内的偶数之和为：" + sum );
}
注意num和sum的区别

0
qq_呵呵_38

2015-09-01 08:51:42

public class dp {
public static void main(String[] args){
int num = 2;
do {
//实现累加求和
num+=num; //这句应该是 sum+=num; sum才是总和！
num = num + 2;
} while (num<=50);
System.out.println(" 50以内的偶数之和为：" + num );
}
}

0
糖菲果

2015-08-22 01:17:46

public class Test {
    public static void main(String[] args){
            int sum = 0;
            for (int i = 0; i <=50; i++) {
                if(i%2==0){//判断是不是偶数
                sum += i;
            }
        }
        System.out.println("50以内的偶数之和为：" + sum );
    }
}
1