Bronze Edition Guide - True BASIC

9. Decision Structures
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Other Decision Structures
The IF-THEN-ELSE structure gives you two possible branches for your decisions. The
program makes a decision and then carries out one of two sets of statements. You can nest
an IF structure inside another if you wish to make additional decisions, but this can be awkward
if you have several related decisions.
True BASIC includes two more decision structures that let you choose among three or more
sets of statements. The programs shown below provide a quick introduction; these programs
are in the TBDEMOS Directory.
The ELSE IF statement expands the IF structure to allow for multiple decisions. Consider
the guessing game played in the GUESS program. In that program there are just two things
that might happen after you guess: the program says you are wrong, or it says you are correct
and the game ends. The program GUESS2 can do one of five things based on your guess:
! Program to play a guessing game.
!
RANDOMIZE
LET answer = Int(Rnd*10) + 1 ! From 1 to 10
PRINT “I’m thinking of a number from 1 to 10.”
PRINT “You have 3 chances to guess it.”
PRINT
FOR chance = 1 TO 3
PRINT “Enter your guess”;
INPUT guess! Get a guess
! Ask for number
IF guess < 1 THEN! Check it out
PRINT “Must be at least 1.”
ELSE IF guess > 10 then
PRINT “Can’t be more than 10.”
ELSE IF guess < answer then
PRINT “Too low.”
ELSE IF guess > answer then
PRINT “Too high.”
ELSE! Must be right
PRINT “Correct!!!”
STOP
END IF
NEXT chance
PRINT “The number was”; answer; “.”
END