4.12. Wrap-Up
You learned that only three types of
control structures—sequence, selection and repetition—are needed to develop any
algorithm. We demonstrated two of C++'s selection statements—the if
single-selection statement and the if...else double-selection
statement. The if statement is used to execute
a set of statements based on a condition—if the condition is true, the
statements execute; if it is not, the statements are skipped. The
if...else double-selection statement
is used to execute one set of statements if a condition is true, and another set
of statements if the condition is false. We then discussed the while repetition statement, where a set of statements are executed
repeatedly as long as a condition is true. We used control-statement stacking to
total and compute the average of a set of student grades with counter- and
sentinel-controlled repetition, and we used control-statement nesting to analyze
and make decisions based on a set of exam results. We introduced assignment
operators, which can be used for abbreviating statements. We presented the
increment and decrement operators, which can be used to add or subtract the
value 1 from a variable. In Chapter
5, Control Statements: Part 2, we continue our
discussion of control statements, introducing the for,
do...while and switch statements.