RosettaCodeData/Task/Knapsack-problem-Continuous/ALGOL-68/knapsack-problem-continuous...

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BEGIN # Knapsack problem: Continuous - based on the EasyLang sample #
MODE ITEM = STRUCT( STRING name, REAL weight, value );
PRIO SWAP = 1;
OP SWAP = ( REF ITEM a, b )VOID: BEGIN ITEM t = a; a := b; b := t END;
OP PRICE = ( ITEM a )REAL: value OF a / weight OF a;
[]ITEM possible items
= ( ( "beef", 3.8, 36 ), ( "pork", 5.4, 43 ), ( "ham", 3.6, 90 ), ( "greaves", 2.4, 45 )
, ( "flitch", 4.0, 30 ), ( "brawn", 2.5, 56 ), ( "welt", 3.7, 67 ), ( "salami", 3.0, 95 )
, ( "sausage", 5.9, 98 )
);
[ LWB possible items : UPB possible items ]ITEM sack items := possible items;
FOR p FROM LWB sack items TO UPB sack items - 1 DO
FOR q FROM p + 1 TO UPB sack items DO
IF PRICE sack items[ q ] > PRICE sack items[ p ] THEN sack items[ p ] SWAP sack items[ q ] FI
OD
OD;
REAL max weight := 15;
FOR p FROM LWB sack items TO UPB sack items - 1 WHILE max weight > 0 DO
REAL w = IF weight OF sack items[ p ] > max weight THEN max weight ELSE weight OF sack items[ p ] FI;
print( ( fixed( w, -6, 2 ), " kg ", name OF sack items[ p ], newline ) );
max weight -:= w
OD
END