1

Purposes:

Learn JAVA1. What is programming languages2. How to solve problems by computers

1. a CS major student, get a degree in BS2. a programmer system manager project leader3. a computer scientist

is worthwhile and doable.

Being

2

Hardware SoftwareTheory1800 AD

Architecture1945 AD

What is Computer Science?

Languages1960 AD

3

Alan Turing (1912-1954) – The Enigma

The man who invented the computer

Image from http://ei.cs.vt.edu/~history/Turing.html

Turing Machines

Turing Award: the Nobel Prize in CS

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Said:

“Turing Machines are human that compute.”

“In logic nothing is accidental”

Ludwig Wittgenstein (1889-1951)

Image from http://www.ags.uci.edu/~bcarver/wgallery.html

5

Hardware

Input device Output device

Central Processor Unit:

Internal Storage

Control Unit+

Arithmetic-Logic Unit(ALU)

6

Software

0 1 1 00 0 0 11 1 0 0

24=16

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A bit logical, Adder (half adder)

1

+) 11 0

1

+) 0

1

0

+) 1

1

0

+) 0

0

A

+) Bc S

A B c S

0 0 0 0

0 1 0 1

1 0 0 1

1 1 1 0

A

BS

c

Adder

AB

8

Full Adder

Ci

A

+) B

Co S

Ci A B Co S

0 0 0 0 0

0 0 1 0 1

0 1 0 0 1

0 1 1 1 0

1 0 0 0 1

1 0 1 1 0

1 1 0 1 0

1 1 1 1 1

AB

S

Co

FullAdder

Ci

9

4 bits Adder

Full Adder

Full Adder

Full Adder

Full Adder

A

B 0

1 1 0 1

0 1 0

1 0 1 1

0

0 1 0

0 1 0

0

1 0 1 1

+) 0 0 1 0

1 1 0 1

10 0

10

Logical Gates for an Adder (half adder)

A

+) Bc S

A B c S

0 0 0 0

0 1 0 1

1 0 0 1

1 1 1 0AND

OR

AND

NOT

B

A

S

c

1

1

0

11 1

11

1

1

10

0

Half-Adder

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Software: 1. Operation systems2. Applications

XP,Unix,VAX

Words

Excel

E.I.

Hello

Java

Hello.javajavacHello.class

(class loader)

Eclipse,NetBean IDE, Sun

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IDE (Integrated Development Environment)1. A customized plain text editor2. Compiler3. Loader4. Debugging tool

Java 2 Software Development Kit (J2SDK)

Eclipse

1. notepad2. javac hello.java3. java hello4. ......

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Solving a problems by computers.

1+2+3+4+..............+98+99+100 = ?

0 + 1 = sum1;

sum1+2=sum2

sum2+3=sum3

sum3+4=sum4

sum4+5=sum5

sum5+6=sum6.............sum99+100 = sum100

0+1=1

1+2=3

3+3=6

6+4=10

10+5=15

15+6=21...............4950+100=5050

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Solving a problems by computers. 0 + 1 = sum1

sum1+2=sum2

sum2+3=sum3

sum3+4=sum4

sum4+5=sum5

sum5+6=sum6.............sum99+100 = sum100

sum = 0sum = sum+1

sum = sum+2

sum = sum+3

sum = sum +4

sum = sum +5.............sum = sum+100

computercan do the samething againand againfast

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Algorithm: a procedure of calculating (manipulate) data

1+2+3+4+ .............. +98+99+100 = ?

sum = 0sum = sum+1sum = sum+2sum = sum+3sum = sum +4sum = sum +5......sum = sum+100

sum = 0;i = 1;while (i <= 100) do the following{

sum = sum + i;i = i+1;

}sum is the answer;

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Graph Reachability

G: (V,E) V: the set of verticesE: the set of edges

15

463

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V = {1,2,3,4,5,6,7}E = {(1,2), (1,3), (1,4) (3,6),(5,6), (5,7)}

Is there a path from 1 to 6 in G?Is there a path from 1 to 7 in G?

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Algorithm for Graph Reachability:

Input G: (V,E), a,b;let S = {a};mark a;while (s {}) do the following

select one element from S; let it be x;remove x from S;

let N = { y : (x,y) in E };if b in N, say “yes” and stop;mark every b in X;set S = S union N;

say “no”;

Is there a path from a to b in G?

JavaC++CFortranFortran90LispAdaCOBOLBASICPascalPolog

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Pr8oblemsSolutions cycle

Problems

System analyst, Project leader

Algorithms

Senior Programmers

Programs in C++ (or any high level Programming Language)

compiler

AssemblyAssembler

Machine code

linkerResults

Customers

ProgrammersSyntaxSemantics

95%(human)

IDE5%(computers)

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Procedure vs ObjectTo write a program is:

To find a way to manipulate data --

• We design procedures • Procedure-Oriented Programming

Statements + functions programs

To find data to manipulate –

• We choose data (object) • Object-Oriented Programming

Classes + Objects programs

(interfaces, methods, attributes…)

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Classes:A class is a concept of something

Vehicle4 wheels, seat, engine, windows……

Truck…………

Sedan…………

SUV…………

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Method & Attribute

class: Method &Attribute

Method: behaviors (operation, functionalities)

Field (attribute): the properties the class

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Objects

Vehicle

SUV

Honda Pilot

011-JAV

instantiation

Class

Object

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A Java Program:// Fig. 2.1: Welcome1.java// Text-printing program.

public class Welcome1 {

// main method begins execution of Java application

public static void main( String args[] ) { System.out.println( "Welcome to Java Programming!" );

} // end method main

} // end class Welcome1

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