Using Flowcharts

Sample Flowchart (without text) 2

Terminator  Starts and ends a process  Only one flow, either departing or entering START STOP 3

Process  Contains calculation or process  Can contain a sequence of consecutive operations  Has a single flow entering and a single flow exiting Calculate average Sum = A+B+C Ave = Sum/3 4

Decision  Condition whose result causes one of multiple calculations or processes  Stated as question with only YES or NO as answer  One flow entering and two flows exiting Is A > B? Yes No 5

Input/Output  Read input or write output  Only one operation, but can have multiple inputs or outputs  One flow entering and one flow exiting Read A,B,C 6

Connector  Brings together separate flows that are coming together to perform the same operation  Multiple flows entering, one flow exiting  Note there is no “disconnector” 7

Let us try an example 8  We want to build a program to calculate the salary of a finical consultant  We need to read the working hours and hourly rate from the consultant  Calculation: Hours*Pay Rate  Output: the gross pay

Quiz : Draw Flowchart  Let’s write a flowchart to detail the process of a user logging into a computer account  What’s the first step?  Determine input and output  Input: userid and password  Output: one of three situations:  Accepted  Incorrect userid  Incorrect password Please use PowerPoint to finish this quiz and upload your answer to blackboard system. 9

So what are our steps?  INPUT userid and password  CALL check of userid  DECISION: is userid valid?  No, send message to user and exit  Yes, continue  CALL check of password, passing userid  DECISION: OK?  No, send message to user and exit  Yes, send message of success and exit 10