Programming and Problem Solving

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Programming and Problem Solving

• Jianhua Yang
• Department of Computer Science
• University of Houston

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Goals

• What is a computer program?
• How to write a program?
• What is an algorithm?
• What is a high-level programming language?
• What is a compiler?
• What is a computer?
• Hardware and software
• Problem-solving method

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1.1 Overview of Programming

• 1. The concept of programming
• Programming
• Computer
• Computer programming
• Computer program

Planning or scheduling the performance of a task
or an event
A programmable device that can store, retrieve,
and process data
The process of planning a sequence of steps for a
computer to follow
A sequence of instructions to be performed by a
computer
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1.1 Overview of Programming

• 2. How to write a program?
• Problem-solving phase
• Implementation phase
• Maintenance phase

• Analysis
• Algorithm
• Verification

• Programming
• Debugging

• Using
• Maintaining

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1.1 Overview of Programming

• Algorithm
• A step-by-step procedure for solving a problem in
  a finite amount of time.

• Insert the key
• Make sure the transmission in Park
• Depress the gas pedal
• Turn the key to the start position
• If the engine starts, release the key
• if it does not, repeat to start
• Or call the mechanic

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1.1 Overview of Programming

• Programs life cycle
• Problem-solving
• Implementation
• Maintenance

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1.1 Overview of Programming

• Programming language
• Documentation
• Information
• Data

A set of rules, symbols, and special words used
to construct a computer program
The written text and comments that make a program
easier for others to understand, use and modify
Any knowledge that can be communicated
Computerized information
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1.1 Overview of Programming
Algorithm
Problem
Program
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1.2 Programming Language

• 1. Programming language

is a language can be used to write a program
which is recognized by a computer
Including machine language, and high-level
language
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1.2 Programming Language

• Compiler
• Source program
• Object program
• Compilation
• Execution

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1.2 Programming Language

• 2. the structure of PL
• Sequence
• Selection
• loop

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1.2 Programming Language

• Sequence

Statement
Statement
Statement
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1.2 Programming Language

• Selection

Statement
Condition
Statement
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1.2 Programming Language

• Loop

Condition
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1.2 Programming Language

• 3. Subprogram

is a program can be executed independently
Statement1 Statement2 Call subprogram Loop Selecti
on Statement3
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1.2 Programming Language

• Example
• Compute the sum of 1!2!3!n!

sum0 s1compute(1!) sumsums1 s2compute(2!)
sumsums2 . sumsumsn
sum0 k1 loop (k ! n1) sumsumcp(k)
kk1
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1.3 What is a computer

• Computer
• Software
• Hardware

System software Developing software
Application software
Central Processing Unit (CPU) Memory Unit
Input/Output Unit Auxiliary Storage Device
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1.3 What is a computer

• Structure of a computer

Input device
Output device
Central Processing Unit
Control Unit
Computing Unit
Auxiliary Storage device
Memory Unit
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1.4 Ethics and Responsibilities in the Computing
Profession

• Software piracy
• Privacy of data
• Use of computer resources
• Software engineering

The unauthorized copying of software
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1.5 Problem-Solving Techniques

• Self study for this part