This document provides examples of algorithms and program development methodologies. It discusses problem solving steps, program development cycles like waterfall method, and control structures like sequence, selection, and loops. Examples provided include finding the largest of three numbers, calculating factorials, and reversing a number. Pseudocode and flowcharts are used to represent the algorithms.

1. UNIT - 3 PROBLEM SOLVING AND OFFICE AUTOMATION

2. Program Program is a collection of instructions that will perform some task.

3. Problem Solving Steps Analyse the problem. Identify the solution for the problem and divide it into small task. Algorithm has to be prepared. Based on the algorithm the program will be created. Then it has to be executed.

4. Program Development Cycle Methodologies Program planning method Waterfall method etc,.

5. Program planning method Specification Review Informal Design Test & Debug Coding Formal Design Maintaining

6. Specification review collect the requirements understand the requirements Informal Design Identifies the major tasks Identifies the subtasks Formal Design It converts the informal design to some format that can be understand by others.

7. Coding It converts the Design into Programs. It translate these programs to machine language. Test & Debug It use sample data to test whether it works properly. It also eliminate the errors.

8. Maintaining It Modifies the programs if necessary.

9. Waterfall method Feasibility Analysis Maintenance Testing Impl Design

10. Feasibility It determines whether it is possible to create the project or not. It also produce the plans and the estimates. Analysis It get the requirements from the customer. It analysis the requirements.

11. Design It is the process of designing how the requirements to be implemented. Implementation It converts the designs into code. After coding it use language translators to compile the code.

12. Testing Here the modules are integrated together. Then the project is tested and find whether it meets the customer/user requirements. Maintenance It make modifications based on the customer feedbacks.

13. Algorithm Algorithm is a finite sequence of instructions required for producing the desired result.

14. Characteristics The steps in the algorithm must be unambiguous . It should be written in sequence. Ensure that the algorithm will terminate. It should conclude after a finite number of steps.

15. Factors used to judge the algorithm Time Memory Accuracy Sequence etc,.

16. Representations Flowcharts Normal English Pseudo code etc,.

17. Example Addition of two numbers Step1: Start Step2: Read a, b Step3: Add the value of a with b and store the result in c. Step4: Display the value of c Step5: Stop

18. Flowcharts It is the pictorial representation of the algorithm.

19. Flowchart Symbols Terminal symbol It is used to represent the start, end of the program logic. Input/Output It is used for input or output. Process Symbol It is used to represent the calculations, data movements, initialization operations etc,.

20. Decision Symbol It is used to denote a decision to be made at that point Flow lines It is used to connect the symbols Connectors It is used to connect the flow lines.

21. Guidelines for preparing flowcharts It should be simple. Standard symbols should be used. The flow lines should not intersect each others. In case of complex flowcharts use the connectors symbols.

22. Only one flow line should enter the process symbol and only one flow line should come out from a process symbol. Only one flow line used with the terminal symbol. START STOP

23. Only one flow line should enter the decision symbol and two or three flowlines may leave from the decision symbol.

24. Benefits of Flowcharts Makes Logic Clear Communication Effective Analysis Useful in coding Useful in Testing etc,.

25. Limits of Flowcharts It is difficult to use flowcharts for large program Difficult to modify Cost etc,.

26. Pseudocode Pseudo means imitates and code means instruction. It is formal design tool. It is also called Program Design Language.

27. Keywords READ,GET PRINT,DISPLAY COMPUTE,CALCULATE

28. Guideline for writing Pseudocode Steps should be understandable Capitalize the keyword. Indent to show hierarchy. End multiple line structure etc,.

29. Example READ a,b C=a+b WRITE C stop

30. Example READ a,b IF a>b PRINT a is greater ELSE PRINT b is greater ENDIF stop

31. Advantage & Disadvantage It can be easily modified It can be understood easily Compare to flowchart it is difficult to understand the program logic.

32. Sequence control structure Flow chart Pseudocode Process 1 Process 2 Process n Design Structures Process 2 Process n Process 1

33. Sequence control structure The instructions are computed in sequence i.e. it performs instruction one after another. It uses top-down approach. Design Structures

34. Example START C=a+b Print c Read a,b STOP

35. SELECTION CONTROL STRUCTURE It is used for making decisions. It allows the program to make a choice from alternative paths. IF …THEN IF …THEN… ELSE CASE etc.,

36. IF…THEN Pseudocode Flow chart IF condition THEN process 1 . . END IF . . If condition NO YES Process 1

37. Example Start Read a If a>0 Print a is Positive Stop no yes

38. IF…THEN…ELSE Pseudocode Flowchart IF condition THEN process 1 . . ELSE process 2 . . END IF . . If condition YES NO Process 1 Process 2

39. Example Start Read a,b If a>b Print a is Greater Print b is Greater Stop no yes

40. CASE structure Pseudocode Flow chart . . CASE Type Case Type-1: Process 1 Case Type-2: Process 2 . . Case Type-n: Process n . . END CASE Type 1 Type 2 Type 3 Process 1 Process 2 Process 3 no no no yes yes yes

41. start stop Read m1,m2,m3 Avg=(m1+m2+m3)/3 If Avg>=60 If Avg>=50 If Avg>=35 Fail Print First Class Print Second Class Print Third Class Example: Finding the Grade

42. Looping control structure It is used to execute some instructions several time based on some condition. WHILE loop Do…WHILE loop etc.,

43. WHILE Loop Pseudocode Flow chart . . WHILE condition . . Body of the loop . . END WHILE Body of The loop condition no yes

44. Example Start Num=0 Num=Num+1 Print Num while Num<5 stop no yes

45. DO…WHILE Loop Pseudocode Flow chart DO . . Body of the loop . . WHILE condition . . END WHILE Body of The loop condition no yes

46. Example Start Num=0 Num=Num+1 Print Num while Num<5 stop no yes

47. Example: Finding the area of a circle Algorithm Step1: Start Step2: Read the value of r Step3: Calculate area = 3.14*r*r Step4: Print area Step5: Stop

48. Pseudocode Set area READ the r COMPUTE area=3.14*r*r PRINT area stop

49. Flowchart START area=3.14*r*r Print area Read r STOP

50. Find the largest among three Numbers Algorithm Step1: Start Step2: Read the value of a, b, c Step3: IF (a>b) and (a>c) THEN print a is largest ELSE IF (b>c) THEN print b is largest ELSE print c is largest Step4: Stop

51. Pseudocode READ a, b, c IF (a>b) and (a>c) THEN WRITE a is largest ELSE IF (b>c) THEN WRITE b is largest ELSE WRITE c is largest ENDIF stop

52. Flowchart START Print b Is largest Read a,b,c stop If (a>b) and (a>c) If b>c Print a Is largest Print c Is largest no yes yes no

54. Finding roots of the Quadratic equation Step:1 Start Step:2 Enter the values of a,b,c Step:3 Find the value of D Using the Formula, D = b*b-4*a*c Step:4 If D is greater than or equal to zero find 2 roots root1  (-b+sqrt(D))/(2*a) root2  (-b-sqrt(D))/(2*a) Step:5 Print root1 & root2 Step:6 If D is less than zero, then print the roots are imaginary Step:7 Stop

55. Pseudocode Set root1,root2 READ the value of a, b, c Find D  b*b-4*a*c IF D>=0 THEN calculate root1=(-b+sqrt(D))/(2*a) root2=(-b-sqrt(D))/(2*a) ELSE Roots are imaginary END IF WRITE root1,root2 Stop

56. Flow chart Start Stop D=b*b-4*a*c Root1=[-b+sqrt(D)]/(2*a) Root2=[-b+sqrt(D)]/(2*a) Read a,b,c Print root1,root2 If D>=0 no yes Print roots are imaginary

58. Swapping two variables Algorithm Step1: Start Step2: Read the value of a, b Step3: c = a a = b b = c Step4: Print the value of a and b Step5: Stop

59. Pseudocode READ the value of a, b To swap use c = a a = b b = c WRITE a, b stop

60. Flowchart START c = a a = b b = c Print a, b Read a, b STOP

61. Swapping two variables without using another variable Algorithm Step1: Start Step2: Read the value of a, b Step3: a = a + b b = a - b a = a - b Step4: Print the value of a and b Step5: Stop

62. Pseudocode READ the value of a, b To swap use a = a + b b = a - b a = a - b WRITE a, b stop

63. Flowchart START a = a + b b = a - b a = a - b Print a, b Read a, b STOP

64. Finding the year is leap year or not Algorithm Step1: Start Step2: Read the value of year Step3: IF year % 4 ==0 THEN print It is a Leap year ELSE print It is not a Leap year Step4: Stop

65. Pseudocode READ year IF year % 4 ==0 THEN WRITE It is a Leap year ELSE WRITE It is not a Leap year ENDIF stop

66. Flowchart Start Read year year % 4 ==0 Print It is a Leap year Print It is not a Leap year Stop no yes

67. Finding the Factorial Algorithm Step1: Start Step2: Read the value of n and set i =1 Step3: While i <= n do fact =fact * i i = i + 1 else Goto step5 Step4: Goto step 3 Step5: print the value of fact Step6: Stop

68. Pseudocode READ the value of n and set i =1 WHILE (i <= n) do fact =fact * i i = i + 1 ENDWHILE Repeat the loop until condition fails WRITE fact stop

69. Flowchart Start Read n i = 1 fact=fact * i i=i+1 Print fact while i<=n stop no yes

70. Finding the Sum of the digits Algorithm Step1: Start Step2: Read the value of n and set i = 0, sum = 0 Step3: While n>0 do r=n%10 sum=sum + r n=n/10 else Goto step5 Step4: Goto step 3 Step5: print the value of sum Step6: Stop

71. Pseudocode READ the value of n and set i =0, sum=0 WHILE (n>0) do r=n%10 sum=sum + r n=n/10 ENDWHILE Repeat the loop until condition fails WRITE sum stop

72. Flowchart Start r = 0,sum=0 r=n%10 sum=sum + r n=n/10 Print sum while n>0 stop no yes Read n

73. Finding the Reverse of a Number Algorithm Step1: Start Step2: Read the value of n and set i = 0, sum = 0 Step3: While n>0 do r=n%10 sum=sum *10 + r n=n/10 else Goto step5 Step4: Goto step 3 Step5: print the value of sum Step6: Stop

74. Pseudocode READ the value of n and set i =0, sum=0 WHILE (n>0) do r=n%10 sum=sum *10 + r n=n/10 ENDWHILE Repeat the loop until condition fails WRITE sum stop

75. Flowchart Start r = 0,sum=0 r=n%10 sum=sum *10 + r n=n/10 Print sum while n>0 stop no yes Read n

76. Armstrong Number Example: 153 1 3 +5 3 + 3 3 =153

77. Finding an Armstrong Number Algorithm Step1: Start Step2: Read the value of n and set a = n, sum = 0 Step3: While n>0 do r=n%10 sum=sum + r*r*r n=n/10 else Goto step5 Step4: Goto step 3 Step5: If a = sum then Print Armstrong Number Else Print It is Not an Armstrong Number Endif Step6: Stop

78. Pseudocode READ the value of n and set a =n, sum=0 WHILE (n>0) do r=n%10 sum=sum + r*r*r n=n/10 ENDWHILE Repeat the loop until condition fails IF a=sum THEN WRITE Armstrong Number ELSE WRITE It is not an Armstrong Number ENDIF stop

79. Flowchart Start a = n,sum=0 r=n%10 sum=sum + r*r*r n=n/10 Print Armstrong No while n>0 stop no yes Read n if a=sum Print It is Not an Armstrong No

80. Fibonacci series Example: 0 1 1 2 3 5 8 11….

81. Finding the Fibonacci series Algorithm Step1: Start Step2: Read the value of n and set f=0,f1=-1, f2=1 Step3: While (f<n) do f=f1+f2 f1=f2 f2=f Print f else Goto step5 Step4: Goto step 3 Step5: Stop

82. Pseudocode READ the value of n and set f=0 ,f1=-1, f2=1 WHILE (f<n) do f=f1+f2 f1=f2 f2=f WRITE f ENDWHILE Repeat the loop until condition fails stop

83. Flowchart Start f=0,f1= -1,f2=1 f=f1+f2 f1=f2 f2=f Print f while f<n stop no yes Read n

84. Conversion of Celsius to Fahrenheit Algorithm Step1: Start Step2: Read the value of Celsius Step3: Fahrenheit = (1.8* Celsius) + 32 Step4: Print Fahrenheit Step5: Stop

85. Pseudocode Set Fahrenheit READ the Celsius COMPUTE Fahrenheit = (1.8* Celsius) + 32 PRINT Fahrenheit stop

86. Flowchart START Fahrenheit = (1.8* Celsius) + 32 Print Fahrenheit Read Celsius STOP

87. Conversion of Fahrenheit to Celsius Algorithm Step1: Start Step2: Read the value of Fahrenheit Step3:Calculate Celsius =(Fahrenheit – 32)/1.8 Step4: Print Celsius Step5: Stop

88. Pseudocode Set Celsius READ the Fahrenheit COMPUTE Celsius =(Fahrenheit – 32)/1.8 PRINT Celsius stop

89. Flowchart START Celsius =(Fahrenheit – 32)/1.8 Print Celsius Read Fahrenheit STOP

90. Finding the sum of odd number between 1 to n Algorithm Step1: Start Step2: Read the value of n and set sum=0,i=1 Step3: While (i<=n) do sum=sum+i i=i+2 else Goto step5 Step4: Goto step 3 Step5: Print sum Step6: Stop

91. Pseudocode READ the value of n and set sum=0,i=1 WHILE (i<=n) do sum=sum+i i=i+2 ENDWHILE Repeat the loop until condition fails WRITE sum stop

92. Flowchart Start sum=0,i=1 sum=sum+i i=i+2 Print sum stop Read n While i<=n

93. Finding the sum of even number between 1 to n Algorithm Step1: Start Step2: Read the value of n and set sum=0,i=0 Step3: While (i<=n) do sum=sum+i i=i+2 else Goto step 5 Step4: Goto step 3 Step5: Print sum Step6: Stop

94. Pseudocode READ the value of n and set sum=0,i=0 WHILE (i<=n) do sum=sum+i i=i+2 ENDWHILE Repeat the loop until condition fails WRITE sum stop

95. Flowchart Start sum=0,i=0 sum=sum+i i=i+2 Print sum stop Read n While i<=n

96. Conversion of Binary number to Decimal Algorithm Step1: Start Step2: Read the value of n and set i = 0, sum = 0 Step3: While n>0 do r=n%10 sum=sum + r*pow(2,i) n=n/10 i=i+1 else Goto step5 Step4: Goto step 3 Step5: print the value of sum Step6: Stop

97. Pseudocode READ the value of n and set i =0, sum=0 WHILE (n>0) do r=n%10 sum=sum + r*pow(2,i) n=n/10 i=i+1 ENDWHILE Repeat the loop until condition fails WRITE sum stop

98. Flowchart Start sum=0,i=0 Print sum stop Read n While n>0 r=n%10 sum=sum + r*Pow(2,i) n=n/10 i=i+1

99. Application software Packages

100. Application software Set of programs, which is used to perform some specific task. Example: Word processor Spreadsheet program Database program etc,.

101. MS-Word Starting MS-Word Start  All Programs  Microsoft Office  Microsoft Office Word

102. Creating a New Document File  New (or) ctrl+N (or) clicking the new button Opening a Document File  Open (or) ctrl+O (or) clicking the open button

103. Saving a New Document File  Save (or) ctrl+S (or) clicking the save button Printing a Document File  Print (or) ctrl+P (or) clicking the open button

104. Moving the Text Ctrl+X (or) clicking the cut button Copying the Text Ctrl+P (or) clicking the copy button

105. Find and Replace Find & Replace Edit  Find and Replace (or) Ctrl+F

106. Formatting the Document Format Menu ( Format  Font) Font size, type, colour, Subscript, Superscript, Spacing,Text Effects etc,. Bullets and Numberings Changing case Borders and Shadings etc,.