import java.util.Scanner;


public class Variables {

	
	public static void main(String[] args) {
		
		/******************************************************************************************************
		 * PRIMITIVE TYPES
		 *
		 ******************************************************************************************************/
		
		
		/* 
		 * 
		 * Variable declaration is stating the variable's type and name. ([variable type] [variable name])
		 * Primitive types are special data types built into the language; they are not objects created from a class.
		 * Java programming language is strongly-typed. This means that all variables must first be declared before they can be used.
		 * 		
		*/
		
		byte firstByte;  // It has a minimum value of -128 and a maximum value of 127 | Size: 1 byte
		short firstShort; // It has a minimum value of -32,768 and a maximum value of 32,767 | Size: 2 bytes 
		int firstInt; // It has a minimum value of -2,147,483,648 and a maximum value of 2,147,483,647 | Size: 4 bytes
		long firstLong; // It has a minimum value of -9,223,372,036,854,775,808 and a maximum value of 9,223,372,036,854,775,807  | Size: 8 bytes
		float firstFloat; // Range is [-3.4x10^-38, -3.4x10^+38] and [+3.4x10^-38, +3.4x10^+38] | Size: 4 bytes
		double firstDouble; // Range is [-1.7x10^-308, -1.7x10^+308] and [+1.7x10^-308, +1.7x10^+308]  | Size: 8 bytes
		boolean firstBoolean; // It has only two possible values: true and false
		char firstChar; // It is a single 16-bit Unicode character.
		
		
		
		/* 
		 * It is not allowed to use keywords as variable names		
		*/
	
		//int int=0;
		//int void=0;
		
		
		
		
		/*
		 * A value can be assigned to a variable with an assignment statement. ([variable name] = [literal])
		 * A literal is the source code representation of a fixed value (e.g. 12, 20.30f, 'c')
		 * 
		 */
		
		firstInt=3;
		firstFloat=10.20f;
		firstChar='c';
		
		
		

		
		/*
		 * Variable initialization is assigning a value to a variable when it is declared. ([variable type] [variable name] = [literal])
		 */
		
		int initializedInt=10;
		float initializedFloat=10.23f;
		char initializedChar='a';
		
		
		
		/*
		 * Uninitialized variables are assigned default values according their data type
		 * int --> 0
		 * float --> 0.0f
		 * char --> '\u0000'
		 * 
		 */
						
		
		/*
		 * 
		 * Casting 
		 * 
		 */
		
		int intValue=1132;
		float  floatValue;
		
		floatValue=intValue;
		floatValue=(float)intValue;
		
		System.out.println(floatValue);
		
		floatValue=12.52f;
		intValue=0;
		
		//intValue=floatValue;
		intValue=(int)floatValue;
		
		System.out.println(intValue);
		
		/*
		 * Arithmetic Operators = +,-,*,/,% 
		 * Integer division returns integer
		 * precedence of operators in Java are the same like in Math
		 * 
		 */
		
		
		int denominator=8;
		int divisor=3;
		int result;
		
		result=denominator/divisor;
		System.out.println(result);
		
		int a=4;
		int b=8;
		int c=4;
		
		result=a+b/c;
		System.out.println(result);

		
		result=(a+b)/c;
		System.out.println(result);
		
		
		/*
		 * 
		 * Overflow
		 */

		int overflowed= 2147483647;
		System.out.println(overflowed);
		overflowed= 2147483647+1;
		System.out.println(overflowed);
		overflowed= 2147483647+2;
		System.out.println(overflowed);
		
		int i = 1000000;
        System.out.println(i * i);
        long l = i;
        System.out.println(l * l);
        //System.out.println(20296 / (l - i));

		
		
		/*
		 * 
		 * Rounding of Floats
		 * 
		 * 
		 */
		
        System.out.println("precision is 8 digits starting from the highest ordered digit: ");
		float PI = 3.141592653589793F ;
	    System.out.println( PI ) ;
	    float x = 1.0F ;
	    System.out.println( x / 3.0F ) ;
	    float af = 1.0F, bf = 0.000000000000000000001F, cf ;
	    cf = af + bf ;
	    System.out.println( cf ) ;
	    
	    
	    float flow = 3.4e38f;
        System.out.print("overflow produces infinity: ");
        System.out.println(flow*10);
        
        flow = 1e-38f * PI * 1e-38f;
        System.out.print("underflow produces 0: ");
        System.out.println(flow);
        
        
        System.out.print("0.0/0.0 is Not-a-Number: ");
        flow = 0.0f/0.0f;
        System.out.println(flow);

		
		
		/******************************************************************************************************
		 * 
		 * STRING
		 *
		 ******************************************************************************************************/
		
		/*
		 * In addition to the eight primitive data types listed above, Java provides character strings. 
		 * Enclosing your character string within double quotes will automatically create a new String object.
		 * 
		 */
		
		
		String firstString="CS is great! ";
		String secondString="No it isn't ";

		
		/*
		 * 
		 * String Concatenation
		 * 
		 */
		
		
		System.out.println(firstString+secondString);
		
		firstString=firstString+33;
		System.out.println(firstString);
		
		System.out.println(firstString.substring(3, 5));
		System.out.println(firstString.toUpperCase());
		
		
		
		
		
		/******************************************************************************************************
		 * 
		 * MATH
		 *
		 ******************************************************************************************************/
		
		
		
		
		System.out.print("2 raised to the power of 3 is ");
		System.out.println(Math.pow(2,3));
		
		System.out.print("2 raised to the power of 3 is ");
		System.out.println(Math.pow(2,3));
		
		System.out.println("Which is larger 2 or 3? " + Math.max(2,3));
		System.out.println("Which is smaller 2 or 3? " + Math.min(2,3));
		
		/******************************************************************************************************
		 * 
		 * SCANNER
		 *
		 ******************************************************************************************************/
		
		
		Scanner keyboard = new Scanner(System.in) ;
		System.out.print("Enter your name: ") ;
		String name = keyboard.nextLine() ;
		System.out.print("Enter your age: ") ;
		int age = keyboard.nextInt() ;
		System.out.print("Enter your lucky real number: ") ;
		float luckynumber = keyboard.nextFloat() ;
		System.out.println("Your name is "+name);
		System.out.println("Your age is "+age);
		System.out.println("Your lucky number "+luckynumber);
		
	
		
	}

}