1. Introduction to Programming Prof. Rommel Anthony Palomino Department of Computer Science and Information Technology Spring 2011

2. Number Systems and Conversions Rommel AB Palomino - UDC Spring 20112  001000000001 0010 0000 2020 21212 2323 2012

3. Number Systems and Conversions Rommel AB Palomino - UDC Spring 20113  Numbers can be represented in many ways  There exist many Numeral System or ways to represent numbers.  Their representation depends on something called BASE  BASE - 1 is the maximum number you can represent using a single digit.  Base 10  Max number using single digit = 10 – 1 = 9

4. Number Systems and Conversions Rommel AB Palomino - UDC Spring 20114  The most well known numeral system is the Decimal System. The one you use everyday.  Base 10  It consist of 10 elements from 0-9.  Besides decimals, there exists others such as:  Binary: Base 2. Uses 2 elements. 0 to 1  Octal: Base 8. Uses 8 elements. 0 to 8.  Hexadecimal: ????

5. Number Systems and Conversions Rommel AB Palomino - UDC Spring 20115  Hexadecimal: Uses up to 16 digits.  From 0 to 15 ??? HexDec 00 11 22 33 …… 99 A10 B11 C12 D13 E14 F15

6. Number Systems and Conversions Rommel AB Palomino - UDC Spring 20116  Hexadecimal: Uses up to 16 digits.  From 0 to 15 ??? HexDec 00 11 22 33 …… 99 A10 B11 C12 D13 E14 F15 FF 16 = 255 10

7. Conversion: Decimal to Binary Rommel AB Palomino - UDC Spring 20117  Method:  Continuously divide the number by 2  get the remainder (which is either 0 or 1)  get that number as a digit of the binary form of the number  get the quotient and divide that number again by 2  repeat the whole process until the quotient reaches 0 or 1  we then get all the remainders starting from the last remainder, and the result is the binary form of the number  NOTE: For the last digit which is already less than the divisor (which is 2) just copy the value to the remainder portion.

8. Conversion: Decimal to Binary Rommel AB Palomino - UDC Spring 20118  Example  Convert 150 10 to Binary  Solution: 10010110 = 150 NumberBaseQuotientRemainder 1502750 2371 2181 290 9241 4220 2210 1201

9. Conversion: Binary to Decimal Rommel AB Palomino - UDC Spring 20119  Method:  we multiply the binary digit to "2 raised to the position of the binary number"  We then add all the products to get the resulting decimal number.

10. Conversion: Binary to Decimal Rommel AB Palomino - UDC Spring 201110  Example  Convert 11100101 2 to Decimal 0: 1 2: 4 5: 32 6: 64 7: 128  Solution: 229

11. Conversion: Binary to Hexadecimal Rommel AB Palomino - UDC Spring 201111  Method:  Partition the binary number into groups of 4 digits (from right to left)  pad it with zeros if the number of digits is not divisible by 4  convert each partition into its corresponding hexadecimal digit

12. Conversion: Binary to Hexadecimal Rommel AB Palomino - UDC Spring 201112  Example  Convert 11100101 2 to Hexadecimal  Solution:

13. Programming Fundamentals Rommel AB Palomino - UDC Spring 201113

14. Introduction to Java Rommel AB Palomino - UDC Spring 201114  The original motivation for Java  The need for platform independent language that could be embedded in various consumer electronic products.

15. Introduction to Java Rommel AB Palomino - UDC Spring 201115  The Java technology is:  A programming language  A development environment  An application environment  A deployment environment

16. Introduction to Java Rommel AB Palomino - UDC Spring 201116  As a development environment, Java technology provides you with a large suite of tools:  A compiler  An interpreter  A documentation generator, etc

17. Java Features Rommel AB Palomino - UDC Spring 201117  Some features of Java:  The Java Virtual Machine  Bytecode  Garbage Collection

18. Java Features Rommel AB Palomino - UDC Spring 201118  Java Virtual Machine (JVM)  an imaginary machine that is implemented by emulating software on a real machine  provides the hardware platform specifications to which you compile all Java technology code

19. Java Features Rommel AB Palomino - UDC Spring 201119  Bytecode  a special machine language that can be understood by the Java Virtual Machine (JVM)  independent of any particular computer hardware, so any computer with a Java interpreter can execute the compiled Java program, no matter what type of computer the program was compiled on

20. Java Features Rommel AB Palomino - UDC Spring 201120  Garbage collection thread  responsible for freeing any memory that can be freed. This happens automatically during the lifetime of the Java program.  programmer is freed from the burden of having to deallocate that memory themselves

21. How a Java Program works? Rommel AB Palomino - UDC Spring 201121

22. Exercise  Write a flowchart for  How to answer and end a phone call in your Cellphone 22Rommel AB Palomino - UDC Spring 2011

23. Questions? 23Rommel AB Palomino - UDC Spring 2011

24. For Next Class Rommel AB Palomino - UDC Spring 201124  We will do our first Java Program and will learn how to use our Programming Environment