Learn to Program with C_ Learn to Program using the Popular C Programming Language ( PDFDrive )

Chapter 4 ■ Programs with Selection Logic
And if hours is 50 and rate is 12 dollars per hour, regular pay is $480 (40 times 12) and overtime
pay is $180 (excess hours 10 times 12 times 1.5). Gross pay is $660 (480 + 180).
The above description could be expressed in pseudocode as follows:
if hours is less than or equal to 40 then
set regular pay to hours x rate
set overtime pay to 0
else
set regular pay to 40 x rate
set overtime pay to (hours – 40) x rate x 1.5
endif
set gross pay to regular pay + overtime pay
We use indentation to highlight the statements to be executed if the condition “hours is less than
or equal to 40” is true and those to be executed if the condition is false. The whole construct is
terminated with endif.
The next step is to convert the pseudocode to C. When we do, we have to make sure that we
stick to C’s rules for writing an if...else statement. In this example, we have to ensure that both
the then and else parts are written as blocks since they both consist of more than one statement.
Using the variables hours (hours worked), rate (rate of pay), regPay (regular pay), ovtPay
(overtime pay), and grossPay (gross pay), we write the C code, thus:
if (hours <= 40) {
regPay = hours * rate;
ovtPay = 0;
} //no semicolon here; } ends the block
else {
regPay = 40 * rate;
ovtPay = (hours - 40) * rate * 1.5;
} //no semicolon here; } ends the block
grossPay = regPay + ovtPay;
Note the two comments. It would be wrong to put a semicolon after the first } since the if
statement continues with an else part. If we were to put one, it effectively ends the if statement
and C assumes there is no else part. When it finds the word else, there will be no if with which
to match it and the program will give a “misplaced else” error.
There is no need for a semicolon after the last } but putting one would do no harm.
Problem: Write a program to prompt for hours worked and rate of pay. The program then
calculates and prints regular pay, overtime pay, and gross pay, based on the above description.
The following algorithm outlines the overall logic of the solution:
prompt for hours worked and rate of pay
if hours is less than or equal to 40 then
set regular pay to hours x rate
set overtime pay to 0
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