subject: Introduction to Programming CS201 Lecture N0-1 [print this page] Introduction to Programming CS201 Lecture N0-1
Hence to design a program properly, we must:
o Analyze a problem statement, typically expressed as a word problem.
o Express its essence, abstractly and with examples.
o Formulate statements and comments in a precise language.
o Evaluate and revise the activities in light of checks and tests and
o Pay attention to detail.
All of these are activities that are useful, not only for a programmer but also for a businessman, a lawyer, a journalist, a scientist, an engineer, and many others.
Let us take an example to demonstrate the use of design recipe:
Suppose we have to develop a payroll system of a company. The company has permanent staff, contractual staff, hourly based employees and per unit making employees. Moreover, there are different deductions and benefits for permanent employees and there is a bonus for per unit making employees and overtime for contractual employees.
We need to analyze the above problem statement. The company has four categories of employees; i.e.; Permanent staff, Contractual staff, hourly based employees and per unit making employees. Further, permanent staff has benefits and deductions depending upon their designation. Bonus will be given to per unit making employees if they make more than 10 pieces a day. Contractual employee will get overtime if they stay after office hours.
Now divide the problem into small segments and calculations. Also include examples in all segments. In this problem, we should take an employee with his details from each category. Let's say, Mr. Ahmad is a permanent employee working as Finance Manager. His salary is Rs.20000 and benefits of medical, car allowance and house rent are Rs.4000 and there is a deduction of Rs.1200. Similarly, we should consider employees from other categories. This will help us in checking and testing the program later on.
The next step is to formulate these statements in a precise language, i.e. we can use the pseudo code and flowcharting. which will be then used to develop the program using computer language.
Then the program should be evaluated by testing and checking. If there are some changes identified, we revise the activities and repeat the process. Thus repeating the cycle, we achieve a refined solution.