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                is => the final value, then the first state-

                ment following the FOR statement is

                executed.  Otherwise, the statement

                following the NEXT statement is executed.

                All FOR loops execute the statements

                between the FOR and the NEXT at least

                once, even in cases like FOR V=1 TO 0.

                Note that expressions (formulas) may be                 315 FOR V=10*N TO

                used for the initial, final and step values             3.4/Q STEP SQR(R)

                in a FOR loop.  The values of the expres-

                sions are computed only once, before the

                body of the FOR...NEXT loop is

                executed.

                When the statement after the NEXT is                    320 FOR V=9 TO 1

                executed, the loop variable is never equal              STEP -1

                to the final value, but is equal to whatever

                value caused the FOR...NEXT loop to

                terminate.  The statements between the

                FOR and its corresponding NEXT in both

                examples above (310 and 320) would be

                executed nine times.

                Error:  do not use nested FOR...NEXT                    330 FOR W=1 TO 10:

                loops with the same index variable.                     FOR W=1 TO 5:NEXT

                                                                        W:NEXT W

                FOR loop nesting is limited only by the

                available memory.  (See Appendix C.)

STATEMENT       SYNTAX/FUNCTION                                         EXAMPLE

GOSUB           GOSUB line number                                       10 GOSUB 910

                Branches to the specified statement (910)

                until a RETURN is encountered; when a

                branch is then made to the statement after

                the GOSUB.  GOSUB nesting is limited

                only by the available memory.

STATEMENT       SYNTAX/FUNCTION                                         EXAMPLE

GOTO            GOTO line number                                        50 GOTO 100

                Branches to the statement specified.

STATEMENT       SYNTAX/FUNCTION                                         EXAMPLE

IF...GOTO       IF expression GOTO line number ...                      32 IF X<=Y+23.4

                Equivalent to IF...THEN, except that                    GOTO 92

                IF...GOTO must be followed by a line

                number, while IF...THEN can be

                followed by either a line number or

                another statement.

STATEMENT       SYNTAX/FUNCTION                                         EXAMPLE

IF...THEN       IF expression THEN line number ...                      IF X<10 THEN 5

                Branches to specified statement if the

                relation is True.

                Executes all of the statements on the                   20 IF X<0 THEN PRINT

                remainder of the THEN if the relation                   "X LESS THAN 0"

                is True.

                WARNING:  The "Z=A" will never be                       25 IF X=5 THEN 50:Z=A

                executed because if the relation is true,

                BASIC will branch to line 50.  If the

                relation is false BASIC will proceed to

                to the line following line 25.