Completed
Push — master ( f6a034...2cb83b )
by Siro Díaz
01:26
created

CircularLinkedList::lastIndexOf()   A

Complexity

Conditions 4
Paths 4

Size

Total Lines 19
Code Lines 12

Duplication

Lines 24
Ratio 126.32 %

Importance

Changes 0
Metric Value
dl 24
loc 19
rs 9.2
c 0
b 0
f 0
cc 4
eloc 12
nc 4
nop 1
1
<?php
2
/**
3
 * DataStructures for PHP
4
 *
5
 * @link      https://github.com/SiroDiaz/DataStructures
6
 * @copyright Copyright (c) 2017 Siro Díaz Palazón
7
 * @license   https://github.com/SiroDiaz/DataStructures/blob/master/README.md (MIT License)
8
 */
9
namespace DataStructures\Lists;
10
11
use DataStructures\Lists\Traits\{CountTrait, ArrayAccessTrait};
12
use DataStructures\Lists\Nodes\SimpleLinkedListNode;
13
use DataStructures\Lists\Interfaces\ListInterface;
14
use OutOfBoundsException;
15
16
/**
17
 * CircularLinkedList
18
 *
19
 * CircularLinkedList is a single and circular linked list that has
20
 * a pointer to the next node and also and last node points to head.
21
 *
22
 * @author Siro Diaz Palazon <[email protected]>
23
 */
24
class CircularLinkedList implements ListInterface {
25
    use ArrayAccessTrait;
26
    private $head;
27
    private $tail;
28
    private $size;
29
    private $current;
30
    private $position;
31
32 View Code Duplication
    public function __construct() {
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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33
        $this->head = null;
34
        $this->tail = &$this->head;
35
        $this->size = 0;
36
        $this->position = 0;
37
        $this->current = &$this->head;
38
    }
39
40
    /**
41
     * Inserts data in the specified position.
42
     *
43
     * @param integer $index the position.
44
     * @param mixed $data the data to store.
45
     */
46 View Code Duplication
    public function insert($index, $data) {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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47
        if($index < 0) {
48
            throw new OutOfBoundsException();
49
        }
50
51
        if($index === 0) {
52
            $this->insertBeginning($data);
53
        } else if($index >= $this->size) {
54
            $this->insertEnd($data);
55
        } else if($index > 0 && $index < $this->size) {
56
            $this->insertAt($index, $data);
57
        }
58
        $this->current = &$this->head;
59
        $this->size++;
60
    }
61
62
    /**
63
     * Inserts at the beginning of the list.
64
     *
65
     * @param mixed $data
66
     */
67
    private function insertBeginning($data) {
68
        $newNode = new SimpleLinkedListNode($data);
69
        if($this->head === null) {
70
            $newNode->next = &$this->head;
71
            $this->head = &$newNode;
72
            $this->tail = &$newNode;
73
        } else {
74
            $this->tail->next = &$newNode;
75
            $newNode->next = $this->head;
76
            $this->head = &$newNode;
77
        }
78
    }
79
80
    /**
81
     * Add a new node in the specified index.
82
     *
83
     * @param integer $index the position.
0 ignored issues
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Bug introduced by
There is no parameter named $index. Was it maybe removed?

This check looks for PHPDoc comments describing methods or function parameters that do not exist on the corresponding method or function.

Consider the following example. The parameter $italy is not defined by the method finale(...).

/**
 * @param array $germany
 * @param array $island
 * @param array $italy
 */
function finale($germany, $island) {
    return "2:1";
}

The most likely cause is that the parameter was removed, but the annotation was not.

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84
     * @param mixed $data the data to be stored.
85
     */
86
    private function insertEnd($data) {
87
        $newNode = new SimpleLinkedListNode($data);
88
        $this->tail->next = &$newNode;
89
        $newNode->next = &$this->head;
90
        $this->tail = &$newNode;
91
    }
92
93
    /**
94
     * Add a new node in the specified index.
95
     *
96
     * @param integer $index the position.
97
     * @param mixed $data the data to be stored.
98
     */
99
    private function insertAt($index, $data) {
100
        $newNode = new SimpleLinkedListNode($data);
101
        $current = $this->head;
102
        $prev = null;
103
        $i = 0;
104
        while($i < $index) {
105
            $prev = $current;
106
            $current = $current->next;
107
            $i++;
108
        }
109
        
110
        $prev->next = &$newNode;
111
        $newNode->next = &$current;
112
    }
113
114
    /**
115
     * Adds at the end of the list new node containing
116
     * the data to be stored.
117
     *
118
     * @param mixed $data The data
119
     */
120
    public function push($data) {
121
        $this->insert($this->size, $data);
122
    }
123
124
    /**
125
     * Adds at the beginning a node in the list.
126
     *
127
     * @param mixed $data
128
     * @return mixed the data stored.
129
     */
130
    public function unshift($data) {
131
        $this->insert(0, $data);
132
    }
133
134
    /**
135
     * Returns the last node data with O(1).
136
     *
137
     * @return mixed null if the list is empty.
138
     */
139
    public function getLast() {
140
        $node = $this->searchLast();
141
142
        return $node !== null ? $node->data : null;
143
    }
144
145
    /**
146
     * Returns the last node with O(1).
147
     *
148
     * @return mixed null if the list is empty.
149
     */
150
    protected function searchLast() {
151
        if($this->head === null) {
152
            return null;
153
        }
154
155
        return $this->tail;
156
    }
157
    
158
    /**
159
     * Returns the data stored in the given position.
160
     * If index is 0 or size - 1 the method is O(1) else O(n).
161
     *
162
     * @param integer $index the position.
163
     * @throws OutOfBoundsException if it is out of limits (< 0 or > size - 1)
164
     * @return mixed the data stored in $index node.
165
     */
166 View Code Duplication
    public function get($index) {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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167
        $node = $this->search($index);
168
        if($node === null) {
169
            return null;
170
        }
171
172
        return $node->data;
173
    }
174
175
    /**
176
     * Returns the node stored in the given position.
177
     * If index is 0 or (size - 1) the method is O(1) else O(n).
178
     *
179
     * @param integer $index the position.
180
     * @throws OutOfBoundsException if it is out of limits (< 0 or > size - 1)
181
     * @return DataStructures\Lists\Nodes\SimpleLinkedListNode the node stored in $index.
182
     */
183
    protected function search($index) {
184
        if($index < 0 || $index > $this->size - 1) {
185
            throw new OutOfBoundsException();
186
        }
187
188
        if($index === 0) {
189
            return $this->head;
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Bug Compatibility introduced by
The expression $this->head; of type null|DataStructures\List...es\SimpleLinkedListNode adds the type DataStructures\Lists\Nodes\SimpleLinkedListNode to the return on line 189 which is incompatible with the return type documented by DataStructures\Lists\CircularLinkedList::search of type DataStructures\Lists\Dat...es\SimpleLinkedListNode.
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190
        }
191
192
        if($index === $this->size - 1) {
193
            return $this->searchLast();
0 ignored issues
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Bug Compatibility introduced by
The expression $this->searchLast(); of type null|DataStructures\List...es\SimpleLinkedListNode adds the type DataStructures\Lists\Nodes\SimpleLinkedListNode to the return on line 193 which is incompatible with the return type documented by DataStructures\Lists\CircularLinkedList::search of type DataStructures\Lists\Dat...es\SimpleLinkedListNode.
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194
        }
195
196
        $i = 0;
197
        $current = $this->head;
198
        while($i < $index) {
199
            $current = $current->next;
200
            $i++;
201
        }
202
203
        return $current;
204
    }
205
206
    /**
207
     *
208
     */
209
    public function contains($data) : bool {
210
        if($this->size === 0) {
211
            return false;
212
        }
213
214
        $current = $this->head->next;
215
        $prev = $this->head;
216
        while($current !== $this->head) {
217
            if($prev->data === $data) {
218
                return true;
219
            }
220
            $prev = $current;
221
            $current = $current->next;
222
        }
223
224
        return false;
225
    }
226
227
    /**
228
     *
229
     */
230 View Code Duplication
    public function indexOf($data) {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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231
        if($this->head === null) {
232
            return false;
233
        }
234
        
235
        $current = $this->head;
236
        $i = 0;
237
        
238
        while($i < $this->size) {
239
            if($current->data == $data) {
240
                return $i;
241
            }
242
243
            $current = $current->next;
244
            $i++;
245
        }
246
247
        return false;
248
    }
249
250
    /**
251
     *
252
     */
253 View Code Duplication
    public function lastIndexOf($data) {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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254
        if($this->head === null) {
255
            return false;
256
        }
257
        
258
        $current = $this->head;
259
        $i = 0;
260
        $pos = false;
261
        while($i < $this->size) {
262
            if($current->data == $data) {
263
                $pos = $i;
264
            }
265
266
            $current = $current->next;
267
            $i++;
268
        }
269
270
        return $pos;
271
    }
272
273
    /**
274
     * Generator for retrieve all nodes stored.
275
     * 
276
     * @return null if the head is null (or list is empty)
277
     */
278 View Code Duplication
    public function getAll() {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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279
        if($this->head === null) {
280
            return;
281
        }
282
        
283
        if($this->head->next === $this->tail) {
284
            yield $this->head->data;
285
        } else {
286
            $current = $this->head;
287
            $i = 0;
288
            while($i < $this->size) {
289
                yield $current->data;
290
                $current = $current->next;
291
                $i++;
292
            }
293
        }
294
    }
295
    
296
    /**
297
     * Delete a node in the given position and returns it back.
298
     *
299
     * @param integer $index the position.
300
     * @throws OutOfBoundsException if index is negative
301
     *  or is greater than the size of the list.
302
     */
303 View Code Duplication
    public function delete($index) {
0 ignored issues
show
Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

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304
        if($index < 0 || ($index > 0 && $index > $this->size - 1)) {
305
            throw new OutOfBoundsException();
306
        }
307
308
        // if the list is empty
309
        if($this->head === null) {
310
            return null;
311
        }
312
        
313
        // if only there is an element
314
        if($this->head->next === $this->head) {
315
            $temp = $this->head;
316
            $this->head = null;
317
            $this->size--;
318
319
            return $temp->data;
320
        }
321
322
        if($index === 0) {
323
            return $this->deleteBeginning();
324
        } else if($index === $this->size - 1) {
325
            return $this->deleteEnd();
326
        } else {
327
            return $this->deleteAt($index);
328
        }
329
    }
330
331
    /**
332
     * Deletes at the beginnig of the list and returns the data stored.
333
     *
334
     * @return mixed the data stored in the node.
335
     */
336 View Code Duplication
    private function deleteBeginning() {
0 ignored issues
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Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
337
        $temp = $this->head;
338
        $this->head = &$this->head->next;
339
        $this->tail->next = &$this->head;
340
        $this->size--;
341
342
        return $temp->data;
343
    }
344
345
    /**
346
     * Deletes at the specified position and returns the data stored.
347
     *
348
     * @param integer $index the position.
349
     * @return mixed the data stored in the node.
350
     */
351
    private function deleteAt($index) {
352
        $i = 0;
353
        $prev = $this->head;
354
        $current = $this->head;
355
        
356
        while($i < $index) {
357
            $prev = $current;
358
            $current = $current->next;
359
            $i++;
360
        }
361
362
        $prev->next = &$current->next;
363
        $this->size--;
364
365
        return $current->data;
366
    }
367
368
    /**
369
     * Deletes at the end of the list and returns the data stored.
370
     *
371
     * @return mixed the data stored in the node.
372
     */
373 View Code Duplication
    private function deleteEnd() {
0 ignored issues
show
Duplication introduced by
This method seems to be duplicated in your project.

Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.

You can also find more detailed suggestions in the “Code” section of your repository.

Loading history...
374
        $prev = $this->head;
375
        $current = $this->head;
376
        
377
        while($current !== $this->tail) {
378
            $prev = $current;
379
            $current = $current->next;
380
        }
381
        
382
        $temp = $current;
383
        $prev->next = &$this->head;
384
        $this->tail = &$prev;
385
        $current = null;
0 ignored issues
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Unused Code introduced by
$current is not used, you could remove the assignment.

This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently.

$myVar = 'Value';
$higher = false;

if (rand(1, 6) > 3) {
    $higher = true;
} else {
    $higher = false;
}

Both the $myVar assignment in line 1 and the $higher assignment in line 2 are dead. The first because $myVar is never used and the second because $higher is always overwritten for every possible time line.

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386
387
        $this->size--;
388
389
        return $temp->data;
390
    }
391
392
    /**
393
     * Deletes the first node of the list and returns it.
394
     *
395
     * @return mixed the data.
396
     */
397
    public function shift() {
398
        return $this->delete(0);
399
    }
400
401
    /**
402
     * Removes and returns the last node in the list.
403
     *
404
     * @return mixed data in node.
405
     */
406
    public function pop() {
407
        return $this->delete($this->size - 1);
408
    }
409
410
    /**
411
     * Removes all nodes of the list. It removes from the beginning.
412
     */
413
    public function clear() {
414
        while($this->head !== null) {
415
            $this->shift();
416
        }
417
    }
418
419
    /**
420
     * Converts/exports the list content into array type.
421
     *
422
     * @return array data stored in all nodes.
423
     */
424
    public function toArray() : array {
425
        $arr = [];
426
        foreach($this->getAll() as $node) {
427
            $arr[] = $node;
428
        }
429
430
        return $arr;
431
    }
432
433
    /**
434
     * Reset the cursor position.
435
     */
436
    public function rewind() {
437
        $this->position = 0;
438
        $this->current = &$this->head;
439
    }
440
441
    /**
442
     * Returns the current node data.
443
     *
444
     * @return mixed
445
     */
446
    public function current() {
447
        return $this->current->data;
448
    }
449
450
    /**
451
     * Key or index that indicates the cursor position.
452
     *
453
     * @return integer The current position.
454
     */
455
    public function key() {
456
        return $this->position;
457
    }
458
459
    /**
460
     * Move the cursor to the next node and increments the
461
     * position counter.
462
     */
463
    public function next() {
464
        ++$this->position;
465
        $this->current = $this->current->next;
466
    }
467
468
    /**
469
     * Returns if the current pointer position is valid.
470
     *
471
     * @return boolean true if pointer is not last, else false.
472
     */
473
    public function valid() {
474
        return $this->position < $this->size;
475
    }
476
477
    /**
478
     * Binds to count() method. This is equal to make $this->tree->size().
479
     *
480
     * @return integer the tree size. 0 if it is empty.
481
     */
482
    public function count() {
483
        return $this->size;
484
    }
485
486
    /**
487
     * Returns the array size.
488
     *
489
     * @return int the length
490
     */
491
    public function size() : int {
492
        return $this->size;
493
    }
494
495
    /**
496
     * Checks if the list is empty.
497
     *
498
     * @return boolean true if is empty, else false.
499
     */
500
    public function empty() : bool {
501
        return $this->size === 0;
502
    }
503
}