Unicode System & Operator in java:

Unicode System

Unicode is a universal international standard character encoding that is capable of representing most of the
world's written languages.
 
Why java uses Unicode System?
Before Unicode, there were many language standards:

• ASCII (American Standard Code for Information Interchange) for the United States.
• ISO 8859-1 for Western European Language.
• KOI-8 for Russian.
• GB18030 and BIG-5 for chinese, and so on.

This caused two problems:        1. A particular code value corresponds to different letters in the various language standards.The encodings for languages with large character sets have variable length.Some common characters are encoded as single bytes, other require two or more byte.
        2. To solve these problems, a new language standard was developed i.e. Unicode System.In unicode, character holds 2 byte, so java also uses 2 byte for characters.

lowest value:\u0000
highest value:\uFFFF

Operator in java:

Operator is a special symbol that is used to perform operations.
Precedence of Operators
Operators                                             Precedence
postfix                                               expr++ expr--
unary                                                 ++expr --expr +expr -expr ~ !
multiplicative                                      * / %
additive                                                    + -
shift                                                   << >> >>>
relational                                            < > <= >= instanceof
equality                                                 == !=
bitwise                                               AND &
bitwise                                                exclusive OR ^
bitwise                                                 inclusive OR |
logical                                                  AND &&
logical                                                  OR ||
ternary                                                    ? :
assignment                                      = += -= *= /= %= &= ^= |= <<= >>= >>>=



Useful Programs:



1) Program of factorial number.

class Operation{
static int fact(int number){
int f=1;
for(int i=1;i<=number;i++){
f=f*i;
}
return f;
}
public static void main(String args[]){
int result=fact(5);
System.out.println("Factorial of 5="+result);
}
}


2) Program of fibonacci series.

class Fabnoci{
public static void main(String...args)
{
int n=10,i,f0=1,f1=1,f2=0;
for(i=1;i<=n;i++)
{
f2=f0+f1;
f0=f1;
f1=f2;
f2=f0;
System.out.println(f2);
}
}
}

3) Program of armstrong number.

class ArmStrong{
public static void main(String...args)
{
int n=153,c=0,a,d;
d=n;
while(n>0)
{
a=n%10;
n=n/10;
c=c+(a*a*a);
}
if(d==c)
System.out.println("armstrong number");
else
System.out.println("it is not an armstrong number");
}
}
 
4) Program of checking palindrome number.

class Palindrome
{
public static void main( String...args)
{
int a=242;
int n=a,b=a,rev=0;
while(n>0)
{
a=n%10;
rev=rev*10+a;
n=n/10;
}
if(rev==b)
System.out.println("it is Palindrome");
else
System.out.println("it is not palinedrome");
}
}
 
5) Program of swapping two numbers without using third variable.



class SwapTwoNumbers{
public static void main(String args[]){
int a=40,b=5;
a=a*b;
b=a/b;
a=a/b;
System.out.println("a= "+a);
System.out.println("b= "+b);
}
}

6) Program of factorial number by recursion
class FactRecursion{
static int fact(int n){
if(n==1)
return 1;
return n*=fact(n-1);
}
public static void main(String args[]){
int f=fact(5);
System.out.println(f);
}
}