Java基本运算符

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-25 15:14
 */
public class Demo01 {
    public static void main(String[] args) {
        // 二元运算符
        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/b);
        System.out.println(a/(double)b);
    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-25 16:03
 */
public class Demo02 {
    public static void main(String[] args) {
        long a = 123123123123123L;
        int b = 123;
        short c = 10;
        byte d = 8;

        System.out.println(a+b+c+d);
        System.out.println(b+c+d);
        System.out.println(c+d);
        System.out.println((double)c+d);
    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-25 18:03
 */
public class Demo03 {
    public static void main(String[] args) {
        // 关系运算符返回的结果

        int a = 10;
        int b = 20;
        int c = 21;

        System.out.println(c%a);    // c / a 的余数

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

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-25 20:00
 */
public class Demo04 {
    public static void main(String[] args) {
        // ++ -- 自增，自减  一元运算符
        int a = 3;

        int b = a++;    // 执行完这一行代码后，先给b赋值，再自增
        System.out.println(a);
        int c = ++a;    // 执行完这一行代码前，先自增，再给c赋值

        System.out.println(a);
        System.out.println(b);
        System.out.println(c);

        // 幂运算 2^3
        double pow = Math.pow(2,3);
        System.out.println(pow);

    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-25 20:10
 */
public class Demo05 {
    // 逻辑运算符
    public static void main(String[] args) {
        // 与(and)   或(or)   非(取反)
        boolean a = true;
        boolean b = false;

        System.out.println("a && b:" + (a && b));   // 逻辑与：两个变量都为真，结果才为true
        System.out.println("a || b:" + (a || b));   // 逻辑或：两个变量有一个为真，则结果才为true
        System.out.println("!(a && b):" + !(a && b));   // 取反：如果是真，则变为假；如果是假，则变为真

        // 短路运算
        int c = 5;
        boolean d = (c<4)&&(c++<4);
        System.out.println(d);
        System.out.println(c);

    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-26 9:11
 */
public class Demo06 {
    public static void main(String[] args) {
        /*
          A = 0011 1100
          B = 0000 1101
----------------------------------
        A&B = 0000 1100
        A|B = 0011 1101
        A^B = 0011 0001
         ~B = 1111 0010

        2*8 = 16
        << *2
        >> /2

         */

        System.out.println(2<<3);
    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-26 9:39
 */
public class Demo07 {
    public static void main(String[] args) {
        int a = 10;
        int b = 20;

        a += b; //  a = a+b
        a -= b; //  a = a-b

        System.out.println(a);

        // 字符串连接
        System.out.println(""+a+b);

        System.out.println(a+b+"");
        
    }
}

package github.demo01;

/**
 * @author subeiLY
 * @create 2021-05-26 9:43
 */
public class Demo08 {
    public static void main(String[] args) {
        // 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 = 80;
        String type = score < 60 ? "不及格" : "及格";
        System.out.println(type);
        
    }
}