/**Array:-
* Used to store more than one values of same data type under a single variable name.
* Each value has a unique index number & start with index zero.
*
* Types:-
* 1)1D Arrays:-
* consist of 1 row and multiple columns.
* for accessing any element:-array name[index no].
* Syntax:
* 1)data_type[] array (or data_type array[]) = new data_type[size](add items:{1,2,3});
*
* 2)2D Arrays:-
* consist of no of rows and no of columns.
* for accessing any element:-array name[row no][column no].
*
* Syntax:
* 1)data_type[][] array (or data_type array[][]) = new data_type[row][column];
*
*
*/
/**
* STRING:-
* Collection of two or more characters.
* in java,for single character and no. of characters are char('') and String("")used
*
* Declaration:-
* String name = new String();
*
* String Methods:-
*
* 1)str(variable).toLowerCase/toUpperCase:- convert string to lower/upper case
* 2)str.trim():- remove white spaces at beginning and end of the string
* 3)str1.equals(str2):- returns true if str1 == str2 &
* str1.equalsIgnoreCase(str2):- returns true if str1 == str2 (ignoring case of the characters)
* 4)str1.replace('x','y'):- replace character 'x' with 'y' in string
* 5)str1.length():- length of str1
* 6)str1.charAt(index):- returns character at index (0 to n) of string.
* 7)str1.concat(str2):- join two strings.
* 8)str1.compareTo(str2):- substracting (str1 - str2)
* 9)str1.substring(n(start index no)) :- gives substring starts from n/
* str1.substring(n(start string),m(end string)):- gives substring starts from n and end at m.
* (but not included m)
* 10)str1.indexOf('x'(char)):-gives index position of x character in string./
* *str1.indexOf('x'(char),n(position)):-gives index position of x character in string after nth position.
* 11)String.ValueOf(p(parameter)/variable):- convert into string object.&
* p.toString():- convert to string of obj. p.
*
*/WRAPPER CLASSES:-* Converts primitive datatype to object type.
* Obtained in Java package:-java.lang.
*
* Simple Type => Wrapper Class
* boolean => Boolean
* char => Character
* double => Double
* float => Float
* int => Integer
* long => Long
*
*EX.
* Converts integer(i) to integer object as
* Integer intVal = new Integer(i);
* //Another Way:- Integer no = Integer.ValueOf();
*
*
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