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Time for an 2014 update…

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Ingy döt Net 2014-01-17 05:32:22 +00:00
parent 372c577f83
commit 09687c4926
2520 changed files with 34227 additions and 7318 deletions
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33
Task/Knapsack-problem-Continuous/D/knapsack-problem-continuous-1.d
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@ -1,10 +1,10 @@
import std.stdio, std.algorithm, std.string, std.conv;
import std.stdio, std.algorithm, std.string;
struct Item {
string name;
real amount, value;
@property real valuePerKG() const pure nothrow {
@property real valuePerKG() @safe const pure nothrow {
return value / amount;
}
@ -14,27 +14,26 @@ struct Item {
}
}
real sum(string field)(in Item[] items) pure nothrow {
real sumBy(string field)(in Item[] items) @safe pure nothrow {
return reduce!("a + b." ~ field)(0.0L, items);
}
void main() {
Item[] raw = [{"beef", 3.8, 36.0},
{"pork", 5.4, 43.0},
{"ham", 3.6, 90.0},
{"greaves", 2.4, 45.0},
{"flitch", 4.0, 30.0},
{"brawn", 2.5, 56.0},
{"welt", 3.7, 67.0},
{"salami", 3.0, 95.0},
{"sausage", 5.9, 98.0}];
// Reverse sorted by Value per amount.
const items = raw.sort!q{a.valuePerKG > b.valuePerKG}.release;
const items = [Item("beef", 3.8, 36.0),
Item("pork", 5.4, 43.0),
Item("ham", 3.6, 90.0),
Item("greaves", 2.4, 45.0),
Item("flitch", 4.0, 30.0),
Item("brawn", 2.5, 56.0),
Item("welt", 3.7, 67.0),
Item("salami", 3.0, 95.0),
Item("sausage", 5.9, 98.0)]
.schwartzSort!(it => -it.valuePerKG)
.release;
immutable(Item)[] chosen;
real space = 15.0;
foreach (item; items)
foreach (const item; items)
if (item.amount < space) {
chosen ~= item;
space -= item.amount;
@ -45,5 +44,5 @@ void main() {
writefln("%10s %7s %7s %7s", "ITEM", "AMOUNT", "VALUE", "$/unit");
writefln("%(%s\n%)", chosen);
Item("TOTAL", chosen.sum!"amount", chosen.sum!"value").writeln;
Item("TOTAL", chosen.sumBy!"amount", chosen.sumBy!"value").writeln;
}