Sharp PC-1403

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T he v al ue ass ig n e d t o a variabl e ca n c h an ge d uri ng the exec u t i o n of a progra m , tak i ng
o n the value t yped i n o r compu t ed duri ng t h e p r ogra m . On e wa y t o ass i gn a var ia ble is
t o u se the INPUT v e r b . I n the fo llowi ng pr ogram , the v a l u e o f A $ will c h a n ge in
re s po n s e t o the d at a type d in answ er to t he inq u i ry "W ORD ? " .
En ter t his pr o gr a m:
10 I N PU T " W ORD ? " ; A $
20 B= LE N ( A $ )
30 PR I NT " WO RD I S " ; B ; " LT R S "
4 0 E N D L..J LJ L
m ea n s space
B efo r e you RUN th e p rog r a m , no t e se v e r a l n e w feat u re s . Li ne 3 0 of thi s prog ram
e x c e eds the 24 - ch a rac te r m a x imum o f th e c om p ut e r ' s d is p l ay . Wh en a li n e i s l onger
th an 24 chara c ters (up t o th e 7 9-ch a r ac t er m aximum) , t he co m pu t e r mov e s th e
c h a r a ct e r s t o t h e l eft a s t h e 24-c h a r ac t e r max imum i s e x ceeded . Thi s doe s no t de s tr oy
t h e p r ev i o us in pu t. Th i s mo v e to the l eft i s r efe r re d t o as ho r izo n tal sc rolli n g .
T he s econd ne w eleme n t in t h i s p r o g ram i s th e u s e o f t h e E ND s tatement to s ign a l the
co m p l e t i o n o f a p ro g ra m . END te ll s th e c o mp u ter t h a t t h e p ro gram i s co m p l eted . I t i s
a lw ays go o d program m i ng p r ac ti ce t o u se a n E ND s t a tem e nt.
A s your pr og r a m s b e c o m e mo re c ompl ex, y ou m ay wi s h t o r evie w t h em befor e
b eg i n nin g exec u t i on . To l ook at your pr og r am , u se t h e LI S T com m a n d . LI ST , whi c h
ca n on ly be u s ed in th e PR Ogram mod e, di sp l ays progr a m s be g i nn i n g w i th the lowe s t
lin e nu m ber .
A $= " T O TAL "
To ass i gn a stri n g va r ia b le , you a l so u s e a l et t e r , f o ll o we d b y a do llar si gn . Do not use
the same letter In designating a numeric and a string fixed variable. Y o u can n o t
de s i g n a t e A a n d A $ in t he s a m e pro gr a m .
R e m ember t h a t each stri n g f ixed va riab le m us t no t e x ceed 7 ch arac t e rs in length :
A = 5
If you a r e un f amili a r w it h t h e u s e of num e ri c a n d s t ri ng v ariab l es i n BA S I C , r e read
th ese sec ti o n s in Ch apter 4 .
U s i ng va r i a b l e s i n program m i ng a ll ows much m ore soph i s t i c ated u s e o f t h e co mpu -
t e r's co mpu ting ab ili t i es .
R e m e m b er , you ass ig n num e r ic fi xed va r i a bles u si n g a n y le tte r s fr o m A to Z :
Example 3- Using Variables in Programming
Programming the Computer