Execute HQ9+: Difference between revisions
→{{header|Forth}}: Add Fortran.
(→{{header|Kotlin}}: Updated example see https://github.com/dkandalov/rosettacode-kotlin for details) |
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then loop 2drop ;</lang>
=={{header|Fortran}}==
This is F77 style except for the END SUBROUTINE HQ9, since F90+ allows the END statement to name its subroutine, and more seriously, the SELECT CASE construction that avoids interminable IF ... THEN ... ELSE IF ... sequences or even, a computed GO TO. The obvious data structure is the CHARACTER type, introduced with F77.
The only difficulty lies in the phasing of the various components of the recital, and especially, producing correct grammar for the singular case. One could simply produce *"1 bottles of beer", or perhaps "1 bottle(s) of beer" but having been hounded for decades by compilers quibbling over syntax trivia, a certain sensitivity has arisen. For this case, the requirement is to append a "s" or not to "bottle" and the task is quite vexing because Fortran does not allow within expressions syntax such as <lang Fortran>"bottle" // IF B.NE.1 THEN "s" FI // " of beer"</lang> so alternative schemes must be devised.
<lang Fortran>
SUBROUTINE HQ9(CODE) !Implement the rather odd HQ9+ instruction set.
CHARACTER*(*) CODE !One operation code per character.
INTEGER I,B !Steppers.
INTEGER A !An accumulator.
A = 0 !Initialised.
DO I = 1,LEN(CODE) !Step through the code.
SELECT CASE(CODE(I:I))!Inspect the operation code.
CASE(" ") !Might as well do nothing.
CASE("+") !Increment the accumulator.
A = A + 1 !Thus. Though, nothing refers to it...
CASE("h","H") !Might as well allow upper or lower case.
WRITE (6,*) "Hello, world!" !Hi there!
CASE("q","Q") !Show the (rather questionable) code.
WRITE (6,*) CODE !Thus.
CASE("9") !Recite "99 bottles of beer"...
DO B = 99,2,-1 !Grammar is to be upheld, so the singular case is special.
WRITE (6,1) B,"bottles"," on the wall,",B,"bottles","." !Two lots: number, text, text.
1 FORMAT (I2,1X,A," of beer",A) !Exhausted by the first triplet, so a new line for the second.
WRITE (6,2) !Now for the reduction.
2 FORMAT ("Take one down, pass it around,") !Announce.
IF (B.GT.2) WRITE (6,1) B - 1,"bottles"," on the wall." !But, not for the singular state.
END DO !Recite the next stanza.
WRITE (6,1) 1,"bottle"," on the wall,",1,"bottle","." !The singular case. No longer "bottles".
WRITE (6,2) !There's nothing so lonesome, morbid or drear,
WRITE (6,*) "No bottles of beer on the wall." !Than to stand at the bar of a pub with no beer.
WRITE (6,*) "Go to the store, buy some more." !Take action.
CASE DEFAULT !Denounce any unknown operation codes.
WRITE (6,*) "Unrecognised code:",CODE(I:I) !This is why a space is treated separately.
END SELECT !So much for that operation code.
END DO !On to the next.
END SUBROUTINE HQ9 !That was odd.
PROGRAM POKE
CALL HQ9("hq9")
END</lang>
To show that the juggling works,
<pre>
Hello, world!
hq9
99 bottles of beer on the wall,
99 bottles of beer.
Take one down, pass it around,
98 bottles of beer on the wall.
98 bottles of beer on the wall,
98 bottles of beer.
Take one down, pass it around,
97 bottles of beer on the wall.
...
Take one down, pass it around,
2 bottles of beer on the wall.
2 bottles of beer on the wall,
2 bottles of beer.
Take one down, pass it around,
1 bottle of beer on the wall,
1 bottle of beer.
Take one down, pass it around,
No bottles of beer on the wall.
Go to the store, buy some more.
</pre>
=={{header|Go}}==
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