Flowchart & Algorithm

Transcription

1 Flowchart & Algorithm 1 What is Algorithm? What is Flowchart? Write down the advantages and disadvantages. Compare them. Flowchart Flowchart is a pictorial or graphical representation of a process. Each step in the process is represented by a different symbol and contains a short description of the process step. The flow chart symbols are linked together with arrows showing the process flow direction. This pictorial representation can give step-by-step solution of the given problem. Advantages Easy to draw. Easy to understand logic. Easy to identify mistakes by non computer person. Easy to show branching and looping. Disadvantages Time consumin. Difficult to modify. Very difficult to draw flowchart for big or complex problems. Algorithm An Algorithm is a finite sequence of well defined steps for solving a problem in systematic manner. It is written in the natural languages like English. Advantages Easy to write. Human readable techniques to understand logic. Algorithms for big problems can be written with moderate efforts. Disadvantages Difficult to debug. Difficult to show branching and looping. Jumping (goto) makes it hard to trace some problems. Comparison: Flowchart It is a pictorial representation of a process. Solution is shown in graphical format. Easy to understand as compared to algorithm. Easy to show branching and looping. Flowchart for big problem is impractical Algorithm It is step wise analysis of the work to be done. Solution is shown in non computer language like English. It is somewhat difficult to understand. Difficult to show branching and looping. Algorithm can be written for any problem

2 2 Explain various symbol used in flowchart. Start / Stop Input / Output (Read / Print) Process Decision making Subroutine Arrows Write an algorithm and Draw a flowchart 3 To find whether given number is even or odd. Step 1 : Input no. Step 2 : If no mod 2=0, goto 4. Step 3 : Print given no is odd, goto 5. Step 4 : Print given no is even. Step 5 : Stop. Read mod 2=0? Print no is Even Print no is Odd

3 4 To enter number still user wants and at the end it should display count of total number of positive, negative and zero entered. Step 1 : Step 2 : Step 3 : Step 4 : Step 5 : Step 6 : Step 7 : Step 8 : Step 9 : Step 10 : Step 11 : Step 12: Initialize pos 0,neg 0,zero 0 If no>0, goto 6 If no<0, goto 7 Increment zero by 1, zero=zero+1.go to 8 Increment pos by 1, pos=pos+1.go to 8 Increment neg by 1, neg=neg+1. Print Do you want to enter more number? Read ans If ans = y, goto 2 Print pos, neg, zero. Stop. pos 0,neg 0,zero 0 no>0? pos pos+1 no<0? neg neg+1 zero zero+1 Do you want to enter more no? Print pos, neg, zero

4 5 To print maximum number from a given 3 numbers. Step 1 : Read a,b, c Step 2 : If a>b, goto 5 Step 3 : If b>c, goto 8 Step 4 : Print c is maximum goto 9 Step 5 : If a>c, goto 7. Step 6 : Print c is maximum, goto 9 Step 7 : Print a is maximum, goto 9 Step 8 : Print b is maximum Step 9 : Stop. Read a, b, c a > b? a>c? b>c? Print max = a Print max = c Print max = b Print max= c

5 6 To find the factorial of a given number. Step 1 : Step 2 : Step 3 : Step 4 : Step 5 : Step 6 : Step 7 : Initialize count 1,fact 1 Calculate fact fact * count. Increment count by 1, count count+1. If count<=no, goto 3. Print fact. Stop. count 1,fact 1 fact fact * count count count + 1 count<=no? Print fact

6 7 To solve series 1!+2!+3!+4!+... +n! Algorithm: Step 1 : Step 2 : Step 3 : Step 4: Step 5: Step 6: Step 7: Step 8: Initialize count=1, fact=1, sum=0 Calculate fact=fact*count Calculate sum=sum + fact. Increment count by 1, count=count+1. If count< no, goto 3. Print sum. Stop. Flowchart: count 1,fact 1,sum 0 fact fact * count sum sum + fact count count + 1 count<=no? Print su