previous Note.)
TABLE 12.1 The Logical OperatorsLogical operators appear between two or more relational tests. For example, here are the first parts
of three if statements that use logical operators:
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if ((age >= 21) && (age <= 65)) {and
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if ((hrsWorked > 40) || (sales > 25000.00)) {and
if (!(isCharterMember)) {If you combine two relational operators with a logical operator or you use the! (not) operator to
negate a relation, the entire expression following the if statement requires parentheses. This is not
allowed:
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if !isCharterMember { /* Not allowed */Of course, there is more to the preceding if statements than what is shown, but to keep things simple
at this point, the if bodies aren’t shown.
Logical operators work just as they do in spoken language. For example, consider the spoken
statements that correspond to the code lines just seen:
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if ((age >= 21) && (age <= 65)) {This could be worded in spoken language like this:
“If the age is at least 21 and no more than 65,...”
And the code
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if ((hrsWorked > 40) || (sales > 25000.00)) {could be worded in spoken language like this:
“If the hours worked are more than 40 or the sales are more than $25000,... “
Similarly,
if (!(isCharterMember)) {