Permutations: Difference between revisions
Content added Content deleted
(Added missing in lazy D version) |
(Better lazy D entry) |
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<lang d>import std.algorithm, std.exception; |
<lang d>import std.algorithm, std.exception; |
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struct Permutations(T) { |
struct Permutations(bool doCopy=true, T) { |
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private immutable size_t num; |
private immutable size_t num; |
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private T[] items; |
private T[] items; |
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return result; |
return result; |
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} |
} |
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this.num = items.length; |
this.num = items.length; |
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} |
} |
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@property T[] front() /*const*/ pure nothrow { |
@property T[] front() /*const*/ pure /*nothrow*/ { |
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static if (doCopy) |
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return items.dup; // not nothrow |
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else |
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| ⚫ | |||
} |
} |
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} |
} |
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Permutations!T permutations( |
Permutations!(doCopy,T) permutations(bool doCopy=true, T) |
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(/*in*/ T[] items) |
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| ⚫ | |||
pure nothrow { |
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return Permutations!(doCopy, T)(items); |
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} unittest { |
} unittest { |
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import std.bigint; |
import std.bigint; |
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void main() { |
void main() { |
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import std.stdio; |
import std.stdio; |
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foreach (p; permutations([1, 2, 3])) |
foreach (p; permutations!false([1, 2, 3])) |
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writeln(p); |
writeln(p); |
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} |
} |
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