unit 1 lecture 1 program design tools 1. algorithm 2. flowchart

unit 1 lecture 1 program design tools 1. algorithm 2. flowchart

• 1.
  PROF.MONIKA GHODEKAR Program DesignTools: Algorithm and Flowchart
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  CONTENTS Program Design Tools: Artof Programming through 1. Algorithms 2. Flowcharts.
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  PROGRAMMING: Programming is theprocess of designing and implementing a sequence of instructions to be executed by a computer. A typical programming task can be divided into two phases: Problem solving phase  produce an ordered sequence of steps that describe solution of problem  this sequence of steps is called an Algorithm Implementation phase  implement the program in some programming language
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  PROGRAM DESIGN TOOLS 1.Algorithms 2. Flowcharts
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  ALGORITHM Definition: A step-by-stepprocedure or formula for solving a problem. Characteristics: •Well-defined: Clear and unambiguous instructions. •Finite: Must terminate after a finite number of steps. •Input/Output: Takes inputs and produces outputs.
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  EXAMPLE 1 OFALGORITHM Algorithm for finding the average of three numbers is as follows − 1. Start 2. Read 3 numbers a, b, c 3. Compute sum = a+b+c 4. Compute average = sum/3 5. Print average value 6. Stop
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  EXAMPLE 2 OFALGORITHM Write an algorithm to determine a student’s final grade and indicate whether it is passing or failing. The final grade is calculated as the average of four marks. Step 1: Start Step 2 : read M1,M2,M3,M4 Step 2: GRADE  (M1+M2+M3+M4)/4 Step 3: if (GRADE < 50) then Print “FAIL” Step 4: if(GRADE>=50) print “PASS” Step 5: End
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  SOME EXAMPLES TOTRY AT HOME : Algorithm to find number is even or odd. Algorithm to calculates the square of a given number. Algorithm to find the largest among three numbers Algorithm to find all the roots of the quadratic equation Algorithm to find the factorial Algorithm to check prime number
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  FLOWCHART A flowchart isa graphical representation of the steps a program takes to process data. we can use several geometric patterns to illustrate the numerous actions the program carries out. With the help of the flowchart, the designer can efficiently segregate the various elements of the process. Also, it facilitates the analysis by giving step-by-step instructions on the problem.
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  FLOWCHART SYMBOLS
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  DRAW A FLOWCHARTTO ADD 2 NUMBERS.
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  EXAMPLE 1: PRINT1 TO 10: Algorithm: Step 1: Start Step 2: Initialize the variable number with 1 Step 3: Print number, Step 4: Increment number by 1, Step 5: If number is not greater than 10 then go back to step 3. Step 6 : End
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  EXAMPLE 2: CONVERTTEMPERATURE FROM FAHRENHEIT ( ) TO CELSIUS ( ) ℉ ℃ Algorithm : Step 1: Start Step 2: Read temperature in Fahrenheit, Step 3: Calculate temperature with formula C=5/9*(F-32), Step 4: Print C. Step 5 : End.
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  EXAMPLE 3: DETERMINEWHETHER A STUDENT PASSED THE EXAM OR NOT:
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  CHECK WHY LAMPIS NOT WORKING?
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  LOGIN PROCESS
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  SOME MORE EXAMPLESTO TRY… 1. Write an algorithm and flowchart to find area of a triangle. 2. Write an algorithm and flowchart to find sum and average of 3 numbers. 3. Write an algorithm and flowchart to find whether a number is even or odd.
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  Algorithm Flowchart An algorithmis the set of rules to be followed by the computer program to obtain desire output from the given input. A flowchart is the graphical representation of the computer program in form of different geometric shapes. It is a bit hard to write an algorithm and also difficult for a common person to understand the flow of the program. It is comparatively easy to make and even easy to understand. It is difficult to detect the errors in the program. It is easy to detect the errors in the program. It doesn't include any geometric shapes. It includes geometric shapes. For huge programs, drawing flowchart is a challenging task whereas an algorithm is more handy. For huge programs, flowchart is difficult to construct. In algorithms, a few predefined rules are used. Flowchart doesn't contain any predefined rules included in them. It is not easy to uniquely represent for loops, if/else statements, etc in algorithms. It is easy to represent branching, loops, if/else statements and nested loops using different geometric shapes in flowchart. Algorithm Vs Flowchart