Presentation on theme: "Prof. B. I. Khodanpur HOD – Dept. of CSE R. V. College of Engineering"— Presentation transcript:
1Prof. B. I. Khodanpur HOD – Dept. of CSE R. V. College of Engineering Prof. B. I. Khodanpur HOD – Dept. of CSE R. V. College of Engineering. ID:Subject: Computer Fundamentals (For EDUSAT)Common Paper for BA / B.Com / B.ScCode: CS-54
2Types of OS: Single User Systems Multi User Systems Operating System can also be classified as,-Single User SystemsMulti User Systems
3Single User Systems: Provides a platform for only one user at a time. They are popularly associated with Desk Top operating system which run on standalone systems where no user accounts are required.Example: DOS
4Multi-User Systems:Provides regulated access for a number of users by maintaining a database of known users.Refers to computer systems that support two or more simultaneous users.Another term for multi-user is time sharing.Ex: All mainframes and are multi-user systems.Example: Unix
5Contents Today's Topic: Problem Solving Techniques We will learn Problem Statement.AlgorithmTypes, ExampleFlowchartSymbols, Examples.
7Problem Statement:Problem Statement help diagnose the situation so that your focus is on the problem, helpful tools at this stage include Algorithms and flowcharts for identifying the expected steps of a process. Therefore to solve any problem,Collect and analyze information and dataTalk with people familiar with the problemIf at all possible, view the problem first handConfirm all findings
8Algorithm:The algorithm is part of the blueprint or plan for the computer program, an algorithm is:“An effective procedure for solving a class of problems in a finite number of steps.”Every algorithm should have the following 5 characteristic feature:InputOutputDefinitenessEffectivenessTermination
9Algorithm (Contd…): To find largest of three numbers Start Read 3 numbers: num1, num2, num3if num1 > num2 then go to step 5if num2 > num3 thenprint num2 is largestelseprint num3 is largestgoto step 6if num1 > num3 thenprint num1 is largestend.
10Algorithm (Contd…):Example: One of the simplest algorithms is to find thelargest number in an (unsorted) list of numbers.High-level description:Assume the first item is largest.Look at each of the remaining items in the list and if it is larger than the largest item so far, make a note of it.The last noted item is the largest in the list when the process is complete.
11Algorithm (Contd…):Formal description: Written in prose but much closer to the high-level language of a computer program, the following is the more formal coding of the algorithm in pseudo code (find the largest number in an (unsorted) list of numbers)Algorithm LargestNumberInput: A non-empty list of numbers L.Output: The largest number in the list L.largest ← L0 for each item in the list L, doif the item > largest, thenlargest ← the itemreturn largest
12Flowchart: What is a Flowchart? The flowchart is a means of visually presenting the flow of control through an information processing systems, the operations performed within the system and the sequence in which they are performed.It is a graphic representation of how a process works, showing, at a minimum, the sequence of steps.Flowcharts are generally drawn in the early stages of formulating computer solutions.
13Flowchart (Contd…): Guideline for drawing a flowchart: Flowcharts are usually drawn using some standard symbols; Some standard symbols, which are frequently required for flowcharting many computer programs are shown below,-
14Flowchart (Contd…): A set of useful standard Flowchart symbols: Rounded boxuse it to represent an event which occurs automatically.Rectangle or boxuse it to represent an event which is controlled within the process. Typically this will be a step or action which is taken.Diamonduse it to represent a decision point in the process.Circleuse it to represent a point at which the flowchart connects with another process.
15ADVANTAGES OF USING FLOWCHARTS: Communication: Flowcharts are better way of communicating the logic of a systemEffective analysis: Problem can be analyzed in more effective way.Proper documentation: Flowcharts serve as a good program documentationEfficient Coding: Flowcharts act as a guide or blueprint during the systems analysis and program development phase.
16ADVANTAGES OF USING FLOWCHARTS (Contd…): Proper Debugging: Flowchart helps in debugging process.Efficient Program Maintenance: The maintenance of operating program becomes easy with the help of flowchart.
22Flowchart for finding the sum of first five natural numbers ( i. e
23Flowchart (Example):Flowchart to find the sum of first 50 natural numbers.
24Flow Chart to find largest of two numbers: StartRead A, BIs A > BYesNoPrint BPrint AEnd
25Flowchart to find the largest of three numbers A,B, and C: NO
26LIMITATIONS OF USING FLOWCHARTS: Complex logic: Sometimes, the program logic is quite complicated. In that case, flowchart becomes complex and clumsy.Alterations and Modifications: If alterations are required the flowchart may require re-drawing completely.Reproduction: As the flowchart symbols cannot be typed, reproduction of flowchart becomes a problem.
27Flowchart (Exercise): Draw a flowchart to depict all steps that you do reach your college.Draw Flowchart for Linear search.