Conditional
Statements
Conditional
statements are statements that check certain conditions (boolean
expressions) before executing certain statements. Graphical representation
using flowcharts (refer to Appendix A) will be used as a tool in helping us
follow the flow of execution in single and multiple selection statements.
4.1
Single
Selection Statement
“To be or not to be, that is the
question.” Or in terms of the single selection statement, we should rephrase it
to “To execute or not to execute, that is the question.” In C, the if statement
is used for single selection. The statement
will be executed if and only if the expression evaluates to true. If more
than one statement needs to be executed, these statements must be enclosed
within braces ({}). These statements are called compound statements.
Format:
if ( expression )
statement;
The above format is represented as:
False
expression
True
statement
Example. Write a program segment that asks for a price
from the user and displays the strings ‘Expensive!’ and ‘Can’t Afford!’ if the
price is greater than or equal to 1000.
To help
us solve the program, let’s first construct our flowchart.
41
Chapter
4
START
get Price
False
Price >=
1000
True
display
“Expensive!”
display “Can’t
Afford!”
END
Translating
our flowchart, we can come up with the following program segment.
main()
{
float
fPrice;
scanf( “%f”, &fPrice );
if ( fPrice >= 1000 )
{
printf(
“Expensive!”
);
printf( “Can’t Afford!” );
}
}
Walang komento:
Mag-post ng isang Komento