Today I learned arithmetic operators, relational operators, self-increasing and self-decreasing operators, and logical operators, and I made progress every day.
The self-increment and self-decrease operator is in front of the variable, firstly executes the self-increase and decrement operation, and then completes the current line of code; after the variable, first executes the code, and then performs the self-increment and decrement operation.
class Demo1 {
public static void main (String [] agrs) {
// operator +-* /
int num = 10;
int num1 = 20;
num = num + num1;
num = num - num1;
num = num * num1;
num = num / num1;
System.out.println(num);
System.out.println(num1);
// The lazy operator + =-= * = / =
int num2 = 12;
int num3 = 4;
num2 + num3;
num2 - = num3;
num2 * = num3;
num2 / = num3;
System.out.println(num2);
System.out.println(num3);
// Relational operator <> <=> =! = ==
boolean ret = true;
ret = 4> 2;
System.out.println(ret);
ret = 3 <6;
System.out.println(ret);
ret = 4 <= 5;
System.out.println(ret);
ret = 3> = 4;
System.out.println(ret);
ret = 5! = 8;
System.out.println(ret);
ret = 4 == 6;
System.out.println(ret);
// Increment and decrement operator
int num4 = 3;
System.out.println(“num4 : " + num4);
System.out.println(”++num4 : " + num4++);
System.out.println("–num4 : " + num4++);
System.out.println("–num4 ：" + --num4);
// logical operator
boolean ret1 = false;
ret1 = 4 > 3 && 5 >1;
System.out.println(ret1);
ret1 = 4 > 1 && 3 > 5;
System.out.println(ret1);
ret1 = 3 > 1 || 4 < 5;
System.out.println(ret1);
ret1 = 4 > 2 || 5 > 2;
System.out.println(ret1);
ret1 = !(5 < 6);
System.out.println(ret1);
ret1 = !(3 > 1);
System.out.println(ret1);
// Logical operator and short circuit principle problem
boolean ret2 = false;
int num5 = 24;
ret2 = ++num5 > 28 && --num5 < 30;
System.out.println("ret2 : " +ret2);
System.out.println("num5 : " +num5);
ret2 = num5 < 27 || ++num5 > 20;
System.out.println("ret2 : " +ret2);
System.out.println("num5 : " +num5);
// Small practice
// numeric characters
boolean ret4 = false;
char ch = '0';
ret4 = ch <= '9' && ch> = '0';
System.out.println(ret4);
//数值0 ~ 9
boolean ret3 = true;
int num6 = 0;
ret3 = num6 >= 0 && num6 <= 9;
System.out.println(ret3);
}
}
