PROBLEM SOLVING AND OFFICE AUTOMATION. A Program consists of a series of instruction that a computer processes to perform the required operation.

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1 UNIT III PROBLEM SOLVING AND OFFICE AUTOMATION Planning the Computer Program Purpose Algorithm Flow Charts Pseudo code -Application Software Packages- Introduction to Office Packages (not detailed commands for examination). COMPUTER PROGRAMMING AND LANGUAGES Computer Program: Computers work on a set of instructions called computer program, which clearly specifies the ways to carry out a task. Developing a Program: A Program consists of a series of instruction that a computer processes to perform the required operation. Program Development Cycle: Before starting the process of writing a program, the programmer has to determine the problem that needs to be solved. There are different approaches to problem solving. One such approach is program development cycle. Program development cycle has the following phases. 1. Analyze/Define the Problem: The problem is analysed precisely and completely. Based on understanding, the developer knows about the scope within which the problem needs to be analysed. 2. Task Analysis: After analyzing the problem, the developer needs to develop various solutions to solve the given problem. From these solutions, an

2 optimum solution is chosen, which can solve the problem comfortably and economically. 3. Designing Phase: After selecting the appropriate solution, algorithm is developed to depict the basic logic of the selected solution. An algorithm depicts the solution in logical steps. Algorithm is represented by flowcharts and pseudo codes. 4. Testing the Algorithm for Accuracy : The purpose of checking algorithm is to identify major logical errors at an early stage, because logical errors are often difficult to detect and correct at later stages. The testing also ensures that the algorithm is a correct one. 5. Coding: The actual coding of the program takes place in the chosen programming language. Depending upon application domain and available resources, a program can be written by using programming languages. 6. Test and debug the program: It is common for the initial program code to contain errors. A program compiler and programmer-designed test data machine tests the code for syntax errors. Depending upon the complexity of the program, several rounds of testing may be required. 7. Documentation and Implementation: Once the progam is free from all the errors, it is the duty of the program developers to ensure that the program is supported by suitable

3 documentation. After documentation, the program is installed on the end use s machine. Analyse Problem Documentation & Implementation Task Analysis Test & Debug the Program Designing Phase Coding Algorithm Testing PROGRAM DEVELOPMENT CYCLE PROBLEM SOLVING TECHNIQUES: Problem solving technique is a set of techniques and graphical tools that helps in providing logic for solving a problem. These tools are used to express the logic of the problem by specifying the correct sequence of all instructions to be carried out There are three important problem solving tools used for program development. They are: i. Algorithms ii. Flowcharts iii. Pseudo codes.

4 i. Algorithms: Algorithms are one the most basic tools that are used to develop the problem solving logic. An algorithm is defined as a finite sequence of explicit instruction that when provided with a set of input values process an output and then terminates. Algorithms can have steps that repeat or require decisions until the task is completed. Example: To find out the largest number among three numbers A, B & C. Step 1: Start Step 2: Read three Numbers A, B & C. Step 3: Find the largest number between A & B and store it in Max_AB. Step 4: Find the larger number between MAX_AB and C and store it in MAX. Step 5: Display MAX. Step 6: Stop. Properties: 1. There must be no ambiguity in any instruction. 2. There should not be any uncertainty about which instruction is to be executed next. 3. The algorithm should conclude after a finite number of steps. 4. The algorithm must be general enough to deal with any contingency.

5 ii. Flowchart: A flowchart is a pictorial representation of an algorithm in which the steps are drawn in the form of different shapes of boxes and the logical flow is indicated by interconnecting arrows. The boxes represent operations and the arrows represent the sequence in which the operations are implemented. Flowchart Symbols: Symbol Symbol Name Description Flow Lines Used to connect Terminal symbols Used to represent start, pause or halt in the program logic. Input/Output Represents the information entering or leaving the system. Processing Represents arithmetic and logical instructions. Decision Represents a decision to be made. Connector Used to join different flow lines. Guidelines for preparing flowcharts:

6 1. The flowchart should be clear, neat and easy to follow. 2. The flowchart must have a logical start and finish. 3. Only one flow line should come out from a process symbol. 4. Only one flow line should enter a decision symbol. However, two or three flow lines may leave the decision symbol. 5. Only one flow line is used with a terminal symbol. 6. Within standard symbols, write briefly and precisely. 7. Intersection of flow lines should be avoided. 8. It is useful to test the validity of the flowchart with normal/unusual test data. Benefits of Flow charts: A flowchart helps to clarify how things are currently working and how they could be improved. It also assists in finding the key elements of a process by drawing clear lines between the end of one process and the start of next one. Reasons for using flowcharts as a problem solving tool are given below: i. Makes Logic Clear.

7 ii. Communication. iii. Effective Analysis. iv. Useful in coding. v. Proper testing and debugging. vi. Appropriate documentation. Limitations of Flowcharts: The limitations of flowcharts are: i. Complex. ii. Costly. iii. Difficult to modify. iv. No update. iii. Pseudo code: Pseudo code is made up of two words: Pseudo and code. It means imitation and code refers to instructions, written in a programming language. Pseudo code is an outline of a program. It uses plain English statements rather than symbols. It is also knows as PDL (Program Design Language). Example: Pseudo code to calculate the area of a rectangle PROMPT the user to enter the height of the rectangle. PROMPT the user to enter the width of the rectangle. COMPUTE the area by multiplying the height with width. DISPLAY the area.

8 STOP. Some of the keywords used in pseudo code are given below: Input: READ, OBTAIN, GET and PROMPT. Output: PRINT, DISPLAY and SHOW. Compute: COMPUTE, CALCULATE and DETERMINE. Initialise: SET and INITIALISE Add ONE: INCREMENT. Benefits of Pseudo code: Since it is independent of any language, it can be used by most programmers. It is easy to develop a program from pseudo code than with a flowchart. It is easy to translate pseudo code into a programming language. Pseudo code is compact and does not tend to run over many pages. Limitations of Pseudo code: It does not provide visual representation of the program s logic. There are no accepted standards for writing pseudo codes. Program Control Structures; Program statements that affect the order in which statements are executed, or that affect whether statements are executed, are called control structures. They affect the flow of simulation code since a control structure

9 evaluates statements and then executes code according to the result. There are 3 control structures. They are: i. Sequence Control Structures: Information flows in a straight line. ii. Selection Control Structures: Decisions are made according to predefined conditions. iii. Repetition Control Structures: Sequence of steps is repeated in a loop until the desired output. i. Sequence Control Structure In a sequence structure, the instructions to be computed follow one another in a logical progression. This structure is denoted by writing one action after another, each action on a line by itself. In addition, all actions aligned with the logical indent. Diagrammatic Representation: Flow Chart Pseudo code

10 Action 1 Action 1 Action 2 Action 3 Action 2 Action 3.. Action N Action N Example: Start X=10, Y=20 Z=X+Y Print Z Stop ii. Selection Control Structure:

11 A selection structure allows the program to make a choice between two alternate paths, whether it is true or false. The first statement of a selection structure is a conditional statement. Once the sequence of steps in the selected path has been carried out, the paths are rejoined and then the next instruction is carried out. Thus, the selection structure has only a single entry and single exit. Diagrammatic Representation: Flow Chart Pseudo code No Is Yes IF Condi tion (Condition is True) THEN true? List of Actions ELSE List of Different Actions Action 2 Action 1 ENDIF..

12 Example: Start Read A, B No Is A>B? Yes Display B Display A Stop iii. Repetition Control Structure: Repetition or loop pattern causes an interruption in the normal sequence of processing. It directs the system to loop back to a previous statement in the program, repeating the same sequence over and again, usually with new data. When a sequence of statements is repeated against a condition, it is said to be in a loop. The looping process can either be one time or multiple times until the desired output is obtained within a single program.

13 Diagrammatic Representation: Flow Chart Repeated Task Con diti on true Pseudo code REPEAT Sequence 1 Sequence 2. False. Sequence N UNTIL condition is false Example: Start Count = 0 Count=count+1 Display count Is count<1 0 Yes Stop

14 Characteristics of Good program: Every computer requires appropriated instruction set to perform the required task. The quality of the processing depends upon the given instructions. Hence, proper and correct instructions should be provided to the computer so that it provides the correct output. Important characteristics of a good program are: Portability Readability Efficiency Structural Flexibility Generality Documentation OFFICE AUTOMATION: Definition: Office Automation refers to the use of integrated computers and communication system to support administrative procedures in an office environment. Commonly used office automations software are: 1. MS-WORD 2. MS-EXCEL 3. MS-ACCESS 4. MS-POWERPOINT

15 Application Software Packages: Application software is a set of programs that used to perform some specific task, such as word processing, drawing figures, maintaining data base etc. 1. Word Processing Programs : Word Processing software allows our computer to be used like an advanced typewriter. We can type and print any letter or report, and then easily change words or move blocks of text around. Example: MS-WORD, Star Writer 2. Spreadsheet Programs : A spreadsheet is made up of cells which can number in thousands and arranged in a grid. Mostly spreadsheet programs also include charting features with tools that allow you to plot the values stored in rows and columns as a graph or chart. Example: MS-EXCEL. 3. Database Programs: Database programs are useful for storing, sorting and retrieving data. Database software lets us enter new data, search through the data. Example: Oracle, MS-ACCESS

16 4. Graphics Programs The graphics programs allow us to sketch any objects. It can be used for scientific drawing. 5. Personal Assistance Package: Personal Assistance package is to use personal computers for storing and retrieving their personal information. It is commonly used to support business people to know the current states of the company. WORD PROCESSOR Word processor is used to produce documents for business or personal use such as newsletter, reports, letters and essays. Features of Word Processor: 1. Fast 2. Editing Features 3. Permanent Storage 4. Formatting features 5. Graphics 6. Object Linking & Embedding (OLE) 7. Spell Check 8. Tables 9. Revise without retyping 10. Mail merge

17 Introduction to MS-WORD: Ms-Word is a Word Processing Program that lets us to create documents such as Letters, Reports, Manuals and Newsletters. Word provides many features that make it easy for creating professional looking documents. The various options provided by Ms-Word are given below: 1. Entering & Editing Text 2. Viewing Documents 3. Formatting Text 4. Formatting Documents 5. Tables 6. Graphics 7. Mail Merge & Labelling 8. Printing Working with Documents The various operations are: 1. Entering Text into the Document 2. Saving a Document 3. Previewing a Document 4. Opening a Document 5. Closing a Document Moving & Copying Text Moving the text is the process of cutting the text from one place and pasting it in the desired location. Copying the text is the process of making the duplication of the existing text in the document. Finding & Replacing Text

18 Finding is the process of locating or searching the required text in the document. Replacing is the process of locating the required text and replaces the located text with specified text. Formatting Documents: Formatting documents means changing the appearance of the document by choosing the difference font types, sizes, colours, alignments etc. Applying Superscript and subscript formats: The superscript format places text slightly above a line of normal printed text. The subscript format places text slightly below a line of normal printed text. We can apply superscript and subscript formats to the selected text, by clicking superscript and subscript check boxes in the effect frames of the font dialog box. Changing the case: The case of a text can be changed by first selecting the text which we want to change, then choosing change case option on the format menu. Changing line spacing: For better presentation of the document, we can give space between the lines in a document. To set line space, we can type the key combinations or choose Paragraph option from the format menu. A Paragraph dialog box is displayed. From that choose Line space drop down list, in which there are six line space formats are available. Choose required one and click ok. Headers & Footers:

19 Headers & Footers allow text, page numbers or section titles, to appear on every page of a document above or below the text area. Headers appear at the top of each page. Footers appear at the bottom of each page. Bullets & Numbering : We can automatically add numbers or bullets to the selected text, by using bullets and numbering option from the format menu, or by clicking the bullets and numbering buttons on the formatting tool bar. Inserting Symbols: We can easily insert special symbols in the document using either the Autocorrect feature or the Symbol option from the Insert Menu. Adding page numbers: We can insert page numbers by using insert-> page numbers options from the menu bar. SPREADSHEET An electronic spreadsheet or spreadsheet is a table of rows and columns into which data is entered. It makes it possible to enter data into a task format, manipulate, stores, print, and create reports and graphics using them. Features of Spreadsheet: 1. Several mathematical, financial and statistical functions are built-in. All complicated calculations can be performed very easily using these functions, facilitating rapid operation. 2. The results of a calculation can be accurate. 3. The worksheet can be quite big in size and any part of it can be viewed or edited.

20 4. Data can also be viewed in the form of graphs. 5. The information entered in a worksheet can be sorted in desired format. 6. We can easily produce reports using the spreadsheet. Introduction to MS-EXCEL Microsoft Excel is the most widely used and versatile spreadsheet package and lets us to organize our data into lists and then summarizes, compare and present our data graphically. Excel allows us 1. to enter and edit data in a worksheet 2. to use functions and formulas to calculate and analyze data 3. to create colorful charts and graphs 4. to save time by combining a series of commands into a single command by using Macros Parts of a Spreadsheet: Columns: Columns are vertical lines of cells. They are named from A to Z afterwards AA to AZ and so on. There are 256 columns in a spreadsheet. Rows: Rows are horizontal lines of cells. A number identifies each row. There are rows. Cells: A cell is a point where the row and the column intersect. The width of cell space can be altered to suit the application. Cell Pointer: It is a highlighted cell boundary that specifies which cell is active at the moment. Working with worksheets: 1. Saving the worksheet 2. Closing the worksheet 3. Editing data in cells 4. Formatting text with Bold, italic and underline

21 5. Adding lines and colours 6. Inserting rows and columns 7. Adding headers and footers in the worksheet 8. Displaying page breaks in a worksheet 9. Working with multiple worksheets 10.Inserting & deleting worksheets 11.Renaming the worksheets 12.Hiding & displaying worksheets 13.Entering formulae in cells