|
1
|
|
|
<?php |
|
2
|
|
|
|
|
3
|
|
|
namespace drupol\phpermutations; |
|
4
|
|
|
|
|
5
|
|
|
/** |
|
6
|
|
|
* Class Permutations. |
|
7
|
|
|
* |
|
8
|
|
|
* @package drupol\phpermutations |
|
9
|
|
|
*/ |
|
10
|
|
|
class Permutations { |
|
11
|
|
|
|
|
12
|
|
|
/** |
|
13
|
|
|
* @var mixed |
|
14
|
|
|
*/ |
|
15
|
|
|
protected $elements; |
|
16
|
|
|
|
|
17
|
|
|
/** |
|
18
|
|
|
* @var int |
|
19
|
|
|
*/ |
|
20
|
|
|
protected $size; |
|
21
|
|
|
|
|
22
|
|
|
/** |
|
23
|
|
|
* Permutations constructor. |
|
24
|
|
|
* |
|
25
|
|
|
* @param array $elements |
|
26
|
|
|
* @param int $size |
|
|
|
|
|
|
27
|
|
|
*/ |
|
28
|
2 |
|
public function __construct(array $elements, $size = NULL) { |
|
|
|
|
|
|
29
|
2 |
|
$this->setElements($elements); |
|
30
|
2 |
|
$size = $size ? $size : count($elements); |
|
|
|
|
|
|
31
|
2 |
|
$this->setSize($size); |
|
32
|
|
|
|
|
33
|
2 |
|
return $this; |
|
|
|
|
|
|
34
|
|
|
} |
|
35
|
|
|
|
|
36
|
|
|
/** |
|
37
|
|
|
* @param int $size |
|
38
|
|
|
*/ |
|
39
|
2 |
|
public function setSize($size) { |
|
40
|
2 |
|
$this->size = $size; |
|
41
|
2 |
|
} |
|
42
|
|
|
|
|
43
|
|
|
/** |
|
44
|
|
|
* @return int |
|
45
|
|
|
*/ |
|
46
|
2 |
|
public function getSize() { |
|
47
|
2 |
|
return (int) $this->size; |
|
48
|
|
|
} |
|
49
|
|
|
|
|
50
|
|
|
/** |
|
51
|
|
|
* @param array $elements |
|
52
|
|
|
* |
|
53
|
|
|
* @return $this |
|
54
|
|
|
*/ |
|
55
|
2 |
|
public function setElements(array $elements) { |
|
56
|
2 |
|
$this->elements = $elements; |
|
57
|
|
|
|
|
58
|
2 |
|
return $this; |
|
59
|
|
|
} |
|
60
|
|
|
|
|
61
|
|
|
/** |
|
62
|
|
|
* @return mixed |
|
63
|
|
|
*/ |
|
64
|
2 |
|
public function getElements() { |
|
65
|
2 |
|
return $this->elements; |
|
66
|
|
|
} |
|
67
|
|
|
|
|
68
|
|
|
/** |
|
69
|
|
|
* @return \Generator |
|
70
|
|
|
*/ |
|
71
|
2 |
|
public function generator() { |
|
72
|
2 |
|
return $this->generate($this->getElements(), $this->getSize()); |
|
73
|
|
|
} |
|
74
|
|
|
|
|
75
|
|
|
/** |
|
76
|
|
|
* @param array $elements |
|
77
|
|
|
* @param $subset_length |
|
78
|
|
|
* |
|
79
|
|
|
* @return \Generator |
|
80
|
|
|
*/ |
|
81
|
2 |
|
protected function generate(array $elements, $subset_length) { |
|
|
|
|
|
|
82
|
2 |
|
$length = \count($elements); |
|
83
|
2 |
|
if($subset_length === null){ |
|
|
|
|
|
|
84
|
|
|
$subset_length = $length; |
|
|
|
|
|
|
85
|
|
|
} |
|
86
|
2 |
|
if($subset_length > $length){ |
|
|
|
|
|
|
87
|
|
|
$subset_length = $length; |
|
|
|
|
|
|
88
|
|
|
} |
|
89
|
2 |
|
$pools = []; |
|
90
|
2 |
|
for ($i = 0; $i < $subset_length; $i++) { |
|
91
|
2 |
|
$pools[] = $elements; |
|
92
|
2 |
|
} |
|
93
|
2 |
|
$productGenerator = $this->product($pools); |
|
94
|
2 |
|
foreach($productGenerator as $key => $indices){ |
|
|
|
|
|
|
95
|
2 |
|
$flipIndices = array_keys(array_flip($indices)); |
|
96
|
2 |
|
if(\count($flipIndices) == $subset_length){ |
|
|
|
|
|
|
97
|
2 |
|
$permute = []; |
|
98
|
2 |
|
foreach($indices as $k => $i){ |
|
|
|
|
|
|
99
|
2 |
|
$permute[] = $elements[$key[$k]]; |
|
100
|
2 |
|
} |
|
101
|
2 |
|
yield $key => $permute; |
|
102
|
2 |
|
} |
|
103
|
2 |
|
} |
|
104
|
2 |
|
} |
|
105
|
|
|
|
|
106
|
|
|
/** |
|
107
|
|
|
* Returns the cartesian product of iterables that were passed as arguments. |
|
108
|
|
|
* |
|
109
|
|
|
* The resulting iterator will contain all the possible tuples of keys and |
|
110
|
|
|
* values. |
|
111
|
|
|
* |
|
112
|
|
|
* @param array|Traversable $iterables |
|
113
|
|
|
* Iterables to combine |
|
114
|
|
|
* |
|
115
|
|
|
* @return \Iterator |
|
|
|
|
|
|
116
|
|
|
*/ |
|
117
|
2 |
|
function product($iterables) { |
|
|
|
|
|
|
118
|
|
|
/** @var \Iterator[] $iterators */ |
|
119
|
2 |
|
$iterators = array_map(array($this, 'toIter'), $iterables); |
|
120
|
2 |
|
$numIterators = count($iterators); |
|
121
|
2 |
|
if (!$numIterators) { |
|
122
|
|
|
yield [] => []; |
|
123
|
|
|
return; |
|
124
|
|
|
} |
|
125
|
2 |
|
$keyTuple = $valueTuple = array_fill(0, $numIterators, null); |
|
126
|
2 |
|
$i = -1; |
|
127
|
2 |
|
while (true) { |
|
128
|
2 |
|
while (++$i < $numIterators - 1) { |
|
129
|
2 |
|
$iterators[$i]->rewind(); |
|
130
|
2 |
|
if (!$iterators[$i]->valid()) { |
|
131
|
|
|
return; |
|
132
|
|
|
} |
|
133
|
2 |
|
$keyTuple[$i] = $iterators[$i]->key(); |
|
134
|
2 |
|
$valueTuple[$i] = $iterators[$i]->current(); |
|
135
|
2 |
|
} |
|
136
|
2 |
|
foreach ($iterators[$i] as $keyTuple[$i] => $valueTuple[$i]) { |
|
137
|
2 |
|
yield $keyTuple => $valueTuple; |
|
138
|
2 |
|
} |
|
139
|
2 |
|
while (--$i >= 0) { |
|
140
|
2 |
|
$iterators[$i]->next(); |
|
141
|
2 |
|
if ($iterators[$i]->valid()) { |
|
142
|
2 |
|
$keyTuple[$i] = $iterators[$i]->key(); |
|
143
|
2 |
|
$valueTuple[$i] = $iterators[$i]->current(); |
|
144
|
2 |
|
continue 2; |
|
145
|
|
|
} |
|
146
|
2 |
|
} |
|
147
|
2 |
|
return; |
|
148
|
|
|
} |
|
149
|
|
|
} |
|
150
|
|
|
|
|
151
|
|
|
/** |
|
152
|
|
|
* Converts any iterable into an Iterator. |
|
153
|
|
|
* |
|
154
|
|
|
* @param array|Traversable $iterable |
|
155
|
|
|
* The iterable to turn into an iterator. |
|
156
|
|
|
* |
|
157
|
|
|
* @return \Iterator |
|
158
|
|
|
*/ |
|
159
|
2 |
|
function toIter($iterable) { |
|
|
|
|
|
|
160
|
2 |
|
if ($iterable instanceof \Iterator) { |
|
161
|
|
|
return $iterable; |
|
162
|
|
|
} |
|
163
|
2 |
|
if ($iterable instanceof \IteratorAggregate) { |
|
164
|
|
|
return $iterable->getIterator(); |
|
165
|
|
|
} |
|
166
|
2 |
|
if (is_array($iterable)) { |
|
167
|
2 |
|
return new \ArrayIterator($iterable); |
|
168
|
|
|
} |
|
169
|
|
|
throw new \InvalidArgumentException('Argument must be iterable'); |
|
170
|
|
|
} |
|
171
|
|
|
|
|
172
|
|
|
/** |
|
173
|
|
|
* @return array |
|
174
|
|
|
*/ |
|
175
|
2 |
|
public function toArray() { |
|
176
|
2 |
|
$results = array(); |
|
177
|
|
|
|
|
178
|
2 |
|
foreach($this->generator() as $value) { |
|
|
|
|
|
|
179
|
2 |
|
$results[] = $value; |
|
180
|
2 |
|
} |
|
181
|
|
|
|
|
182
|
2 |
|
return $results; |
|
183
|
|
|
} |
|
184
|
|
|
|
|
185
|
|
|
} |
|
186
|
|
|
|
This check looks for
@paramannotations where the type inferred by our type inference engine differs from the declared type.It makes a suggestion as to what type it considers more descriptive.
Most often this is a case of a parameter that can be null in addition to its declared types.