Java基础-运算操作

运算操作

package operator;

public class Demo01 {
    public static void main(String[] args) {
        // 二元运算
        // Ctrl + D :复制当前行到下一行
        int a = 10;
        int b = 20;
        int c = 25;
        int d = 25;

        System.out.println(a+b);
        System.out.println(a-b);
        System.out.println(a*b);
        System.out.println(a/(double)b);//0.5被四舍五入了

    }
}

package operator;

public class Demo02 {
    public static void main(String[] args) {
        long a = 1232323333332L;
        int b = 123;
        short c = 10;
        byte d = 8;

        System.out.println(a+b+c+d);//long  //有高级别的类型出现自动转换成高级别类型
        System.out.println(b+c+d);//int
        System.out.println(c+d);//int   两个都不是INT类型，转换成INT类型
        //cast 转换
    }
}

package operator;

public class Demo03 {
    public static void main(String[] args) {
        //关系运算符返回的结果：正确，错误    布尔值
        //条件判断
        int a = 10;
        int b = 20;
        int c = 21;
        System.out.println(c%a);//取余，模运算

        System.out.println(a>b);
        System.out.println(a<b);
        System.out.println(a==b);
        System.out.println(a!=b);

    }
}