Exercises - using logical expressions, Concatenation operators, Using concatenation operators – IBM SC34-5764-01 User Manual

Page 49

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\___________________/

/

true

/

\_____________________________/

true

As a result, when you run the program, it produces the result:

Go skiing.

Exercises - Using Logical Expressions

A student applying to colleges has decided to evaluate them according to the following specifications:

IF

(inexpensive | scholarship) & (reputable | nearby)

THEN

SAY

"I'll consider it."

ELSE

SAY

"Forget it!"

A college is inexpensive, did not offer a scholarship, is reputable, but is more than 1000 miles away.
Should the student apply?

ANSWER

Yes. The conditional instruction works out as follows:

IF

(inexpensive | scholarship) & (reputable | nearby)

THEN ...

\__________/ \___________/

\_________/ \______/

true

false

true

false

\___________/

\_________/

true

true

\_________________________/

true

Concatenation Operators

Concatenation operators combine two terms into one. The terms can be strings, variables, expressions, or
constants. Concatenation can be significant in formatting output.

The operators that indicate how to join two terms are as follows:

Operator

Meaning

blank

Concatenates terms and places one blank between them. If more than one blank separates terms,
this becomes a single blank. For example:

SAY true

blue

/* result is TRUE BLUE */

||

Concatenates terms with no blanks between them. For example:

(8 / 2)||(3 * 3)

/* result is 49

*/

abuttal

Concatenates terms with no blanks between them. For example:

per_cent'%'

/* if per_cent = 50, result

is 50%

*/

You can use abuttal only with terms that are of different types, such as a literal string and a
symbol, or when only a comment separates two terms.

Using Concatenation Operators

One way to format output is to use variables and concatenation operators as in the following example.

Using Variables and Expressions

Chapter 3. Using Variables and Expressions

27

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