Inputs and operators

Input from keyboard:

1 import java.util.*; // Reference Scan         2 Scanner sc=new Scanner (system.in); // defining an input scanner 3 System.out.print ("Please enter a number:"); 4 int num=sc.nextint (); //  5 String str=sc.next (); // reading the input string

Arithmetic operators:

                float Num1=12.45f;int num2=15; System.out.println (NUM1+NUM2); String str= "AA"; System.out.println (STR+NUM2); System.out.println (4.56-0.16); long num3=5l; System.out.println (NUM3*NUM1); int num4=7,num8=2; System.out.println (NUM4/NUM8); System.out.println (num4%3);

Self-increment decrement operator:

+ +-Same as + +

B=++a equivalent to A=a+1,b=a

b=a++ equivalent to B=a,a=a+1

int a=1;
int B, C;
b=a++;
System.out.println ("b=" +b+ "\ta=" +a);
A=1;
C=++a;
System.out.println ("c=" +c+ "\ta=" +a);

Results:

——

Comparison operators:

 1  char  char1= ' A ', char2= ' B ' ; 2  System.out.println (char1>char2);  3  ; 4  System.out.println (num1<num2);  5  System.out.println (' c ' = = ' C '  6  System.out.println (479>=426 7  System.out.println (12.45<=45.5    8  System.out.println (' y '! = ' t '); 

Logical operators:

Logic with:

&&:

1: When both sides at the same time to really return the result is true.

2: False on one side, return result is false

&: When the left value is false, the expression on the right still runs the check result is true or false

Logical OR:

|| ：

1: When both sides are false at the same time, the return result is false.

2: One side appears true the return result is true.

        intNum1=10,num2=5; Booleanreg=false; Booleanreg1=true&& (reg=num1>num2); System.out.println (REG1+ "\ t reg=" +reg); Reg=false; BooleanReg2=false&& (reg=num1>num2); System.out.println (REG2+ "\ t reg=" +reg); Reg=false; Booleanreg3=true& (reg=num1>num2); System.out.println (Reg3+ "\ t reg=" +reg); Reg=false; Booleanreg4=false& (reg=num1>num2); System.out.println (REG4+ "\ t reg=" +reg); System.out.println (!true);

Inputs and operators