package operator;
//逻辑运算符
public class Demo05 {
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));//逻辑与运算:两个变量都为真,结果才为true
System.out.println("a || b:"+ (a||b));//逻辑或运算:两个变量有一个为真,则结果才为true
System.out.println("! (a && b):"+ (a && b));//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 operator;
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*2*2
效率提高!!!
<< *2
>> /2
0000 0000 0
0000 0001 1
0000 0010 2
0000 0011 3
0000 0100 4
0000 1000 8
0001 0000 16
*/
System.out.println(2<<3);
}
}
//位运算符
package operator;
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);
//字符串连接符 + , String
System.out.println(a+b);
System.out.println(""+a+b);
System.out.println(a+b+"");
}
}