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Error in variable Declaration

  All declaration problem

If int greater than size we got error->error: integer number too large

    int x=2147483648;

error: integer number too large

    int x=-2147483649;

error: incompatible types: boolean cannot be converted to int

    int x=true;

error: incompatible types: int cannot be converted to boolean

    boolean x=10;

error: incompatible types: possible lossy conversion from double to long

  long x=10.88;

error: cannot find symbol

    boolean x=True;

              ^

  symbol:   variable True







: error: incompatible types: int cannot be converted to boolean

  if(x){

      ^

: error: incompatible types: int cannot be converted to boolean

  while(x){

Above the last both error valid in c and C++ but error in java

Size of char in java 2 byte because java is unicode based but c and c++ are ascii code based language

System.out.println(Character.BYTES);//2byts

error: incompatible types: possible lossy conversion from long to int

  int z=10l;

incompatible types: possible lossy conversion from double to float

      float a=233.0;

              ^

: error: incompatible types: possible lossy conversion from double to float

  float b=33.0333;

Because after decimal value consider as double

Ans-> suffix with f or F both

double d=22.333333D; this convention no required because double is considered already double 

Double is valid for only decimal values not for octal and hexadecimal.

Double x=0234.34555;

Output is->234.34555

It is consider as decimal not as octal value;

error: malformed floating point literal

    double e=0x234.3444;

Double 03432; is valid because here not (.) floating point it is consider as octal

double e=0234;

    System.out.println(e);

Output is 256

If 

Double e=0345.0;

Consider as integer here floating point is present;

Output is 0345.0

Double e=0xface;

Is valid because here not a floating point

double e=0xface;

    System.out.println(e);

Output is ->64206

error: malformed floating point literal

    double e=0xface.0;

Because hexadecimal not consider double

error: cannot find symbol

  char a=x;

   Ans-char a=’x’;

error: incompatible types: String cannot be converted to char

  char a="x";

Ans-char a=’x’

error: unclosed character literal

  char a='ab';

          ^

: error: unclosed character literal

  char a='ab';

            ^

: error: not a statement

  char a='ab';

error: ';' expected

  char a='a''b';

Char lateral enclosed in single inverted comma only on character at a time.

char c=0xface; valid

char c=01245;valid

char c='\u0061';we can use char literal in unicode representation ‘\u 4digit hexadecimal number’;

Every escape character is char literal;

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