1 | <?php |
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10 | class Fibonacci extends Combinatorics implements \Iterator, \Countable |
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11 | { |
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12 | /** |
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13 | * The maximum limit. |
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14 | * |
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15 | * @var int |
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16 | */ |
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17 | protected $max; |
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18 | |||
19 | /** |
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20 | * The previous element. |
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21 | * |
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22 | * @var int |
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23 | */ |
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24 | private $previous = 1; |
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25 | |||
26 | /** |
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27 | * The current element. |
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28 | * |
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29 | * @var int |
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30 | */ |
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31 | private $current = 0; |
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32 | |||
33 | /** |
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34 | * The current key. |
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35 | * |
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36 | * @var int |
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37 | */ |
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38 | private $key = 0; |
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39 | |||
40 | /** |
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41 | * Fibonacci constructor. |
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42 | */ |
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43 | 2 | public function __construct() |
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44 | { |
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45 | 2 | $this->setMaxLimit(PHP_INT_MAX); |
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46 | 2 | } |
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47 | |||
48 | /** |
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49 | * {@inheritdoc} |
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50 | */ |
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51 | 2 | public function current() |
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52 | { |
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53 | 2 | return $this->current; |
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54 | } |
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55 | |||
56 | /** |
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57 | * {@inheritdoc} |
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58 | */ |
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59 | public function key() |
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60 | { |
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61 | return $this->key; |
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62 | } |
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63 | |||
64 | /** |
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65 | * {@inheritdoc} |
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66 | */ |
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67 | 2 | public function next() |
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68 | { |
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69 | 2 | list($this->current, $this->previous) = [$this->current + $this->previous, $this->current]; |
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70 | 2 | ++$this->key; |
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71 | 2 | } |
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72 | |||
73 | /** |
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74 | * {@inheritdoc} |
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75 | */ |
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76 | 2 | public function rewind() |
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77 | { |
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78 | 2 | $this->previous = 1; |
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79 | 2 | $this->current = 0; |
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80 | 2 | $this->key = 0; |
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81 | 2 | } |
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82 | |||
83 | /** |
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84 | * {@inheritdoc} |
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85 | */ |
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86 | 2 | public function valid() |
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87 | { |
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88 | 2 | return $this->current < $this->getMaxLimit(); |
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89 | } |
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90 | |||
91 | /** |
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92 | * {@inheritdoc} |
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93 | */ |
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94 | 2 | public function count() |
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95 | { |
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96 | 2 | return count($this->toArray()); |
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97 | } |
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98 | |||
99 | /** |
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100 | * Convert the iterator into an array. |
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101 | * |
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102 | * @return array |
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103 | * The elements |
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104 | */ |
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105 | 2 | public function toArray() |
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115 | |||
116 | /** |
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117 | * Set the maximum limit. |
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118 | * |
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119 | * @param int $max |
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120 | * The limit |
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121 | */ |
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122 | 2 | public function setMaxLimit($max) |
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126 | |||
127 | /** |
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128 | * Get the maximum limit. |
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129 | * |
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130 | * @return int |
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131 | * The limit |
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132 | */ |
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133 | 2 | public function getMaxLimit() |
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137 | } |
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138 |