第五话-运算符

运算符总结

代码demo

package operator;

public class Demo01 {
    public static void main(String[] args) {
        //二元运算符
        //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);

        //运算符计算后类型转换
        long a1 = 123123123123L;
        int b1 = 123;
        short c1 = 10;
        byte d1 = 8;
        System.out.println(a1+b1+c1+d1); //Long
        System.out.println(b1+c1+d1);    //Int
        System.out.println(c1+d1);       //Int

        //关系运算符返回的结果： 正确，错误 布尔值
        int a2 = 10;
        int b2 = 20;
        int c2 = 21;
        System.out.println(c2%b2);
        System.out.println(a2>b2);
        System.out.println(a2>  /2
        0000 0010  2
        0000 0100  4
        0000 1000  8
        0001 0000  16
         */
        System.out.println(2<<3); //2 (*2)三次

        //扩展赋值运算符：+=,-=,*=,/=
        int aaa = 10;
        int bbb = 20;
        aaa+=bbb; //aaa = aaa + bbb
        System.out.println(aaa+","+bbb);

        //字符串连接符 +
        System.out.println(aaa+bbb+"");
        System.out.println(""+aaa+bbb);

        //三元运算符: x ? y : z
        // 如果x==true，则结果为y，否则结果为z
        int score = 50;
        String type = score<60 ? "不及格" : "及格";
        System.out.println(type);

    }
}