Collect and sort square numbers in ascending order from three lists: Difference between revisions

Content added Content deleted
m (fix braces)
(→‎{{header|ALGOL 68}}: Use new ALGOL 68-rows library)
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=={{header|ALGOL 68}}==
=={{header|ALGOL 68}}==
{{libheader|ALGOL 68-rows}}
<lang algol68>BEGIN # construct a list of the squares from some other lists #
<lang algol68>BEGIN # construct a list of the squares from some other lists #
# lists are represented by arrays in this sample #
# lists are represented by arrays in this sample #
# displays a list of numbers #
PR read "rows.incl.a68" PR # sorting and printing utilities #
PROC show = ( []INT list )VOID:
FOR i FROM LWB list TO UPB list DO print( ( " ", whole( list[ i ], 0 ) ) ) OD;
# in-place quick sort an array of integers #
PROC quicksort = ( REF[]INT a, INT lb, ub )VOID:
IF ub > lb THEN
# more than one element, so must sort #
INT left := lb;
INT right := ub;
# choosing the middle element of the array as the pivot #
INT pivot := a[ left + ( ( right + 1 ) - left ) OVER 2 ];
WHILE
WHILE IF left <= ub THEN a[ left ] < pivot ELSE FALSE FI DO left +:= 1 OD;
WHILE IF right >= lb THEN a[ right ] > pivot ELSE FALSE FI DO right -:= 1 OD;
left <= right
DO
INT t := a[ left ];
a[ left ] := a[ right ];
a[ right ] := t;
left +:= 1;
right -:= 1
OD;
quicksort( a, lb, right );
quicksort( a, left, ub )
FI # quicksort # ;


# construct the lists of numbers required by the task #
# construct the lists of numbers required by the task #
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, ( 75, 121, 75, 144, 35, 16, 46, 35 )
, ( 75, 121, 75, 144, 35, 16, 46, 35 )
);
);
# find the elements of the lists that are squares #
# find the elements of the lists that are squares #
INT r pos := 0;
INT r pos := 0;
REF[]INT result := HEAP[ 1 : 0 ]INT; # start with an empty list of squares #
REF[]INT squares := HEAP[ 1 : 0 ]INT; # start with an empty list #
FOR i FROM LWB list TO UPB list DO
FOR i FROM LWB list TO UPB list DO
FOR j FROM LWB list[ i ] TO UPB list[ i ] DO
FOR j FROM LWB list[ i ] TO UPB list[ i ] DO
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THEN # have a square #
THEN # have a square #
r pos +:= 1;
r pos +:= 1;
IF r pos > UPB result THEN
IF r pos > UPB squares THEN
# the result array isn't big enough - make a larger one #
# the squares array isn't big enough - make a larger one #
REF[]INT new result := HEAP[ 1 : UPB result + 10 ]INT;
REF[]INT new squares
new result[ 1 : UPB result ] := result;
:= HEAP[ 1 : UPB squares + 10 ]INT;
result := new result
new squares[ 1 : UPB squares ] := squares;
squares := new squares
FI;
FI;
result[ r pos ] := n
squares[ r pos ] := n
FI
FI
OD
OD
OD;
OD;
QUICKSORT squares FROMELEMENT 1 TOELEMENT r pos;
quicksort( result, 1, r pos ); # sort the squares #
show( result[ 1 : r pos ] )
SHOW squares[ 1 : r pos ]
END</lang>
END</lang>
{{out}}
{{out}}
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