算数运算符 ⭐
package study; /** * */ public class TestDemo { public static void main(String[] args) { System.out.println(5/2); System.out.println(5.0/2); System.out.println((float)5/2); System.out.println((float)(5/2)); } }
控制台运行结果:
package study; /** * */ public class TestDemo { public static void main(String[] args) { System.out.println(10%3); System.out.println(-10%3); System.out.println(10%-3); System.out.println(-10%-3); } }
JAVA中的异常
package study; /** * */ public class TestDemo { public static void main(String[] args) { // System.out.println(10%3); // System.out.println(-10%3); // System.out.println(10%-3); // System.out.println(-10%-3); System.out.println(5/0); } }
package study; /** * */ public class TestDemo { public static void main(String[] args) { // System.out.println(10%3); // System.out.println(-10%3); // System.out.println(10%-3); // System.out.println(-10%-3); // System.out.println(5/0); int a = 10; int b = ++a; //a 先++ 后赋值 System.out.println(b);// a = 11 , b = 11 int c = a ++; //a 先赋值,后++ System.out.println(c);// c = 11 , a = 12 } }
比较运算符⛅
package study; /** * */ public class TestDemo { public static void main(String[] args) { int a = 10; int b = 20; System.out.println(a == b); System.out.println(a != b); System.out.println(a < b); System.out.println(a > b); System.out.println(a >= b); System.out.println(a <= b); }
逻辑运算符 🌈
package study; /** * */ public class TestDemo { public static void main(String[] args) { //逻辑与 && int a = 10; int b = 20; int c = 30; // System.out.println(a < b && b < c); //逻辑或 || int d = 10; int e = 20; int f = 30; System.out.println(d < e || e < f); }
表达式1 && 表达式2
必须保证两个表达式都为真,整体才是真
表达式1 || 表达式2
只有一个表达式为真,那么整体就是真
!:非,后面只能跟布尔类型的数据
package study; /** * */ public class TestDemo { public static void main(String[] args) { //逻辑与 && int a = 10; int b = 20; // System.out.println(!a < b); boolean flg = true; System.out.println(!flg); } }
进制转换 💧
几进制就是用几个数字表示
按位与 & :相当于乘法
按位或 | : 把它看成加法
按位异或^: 一样就是0,不一样就是1
按位取反~:把0变成1,1变成0
移位运算符 ⚡
