某些业务场景下,我们会用到组合穷举方法,这里整理几个穷举方法
1、不限顺序的数组组合穷举:
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<?php /** * @param $arr 需要组合数组 * @param int $num 组合元素个数 * @return array */ function getSequenceAry($arr,$num=1) { $count = count($arr); $min = min($count,$num); if($min<1){ return false; } $return =array(); for(;$min>=1;$min--){ $arrRet = array(); $max = $count-($min-1); for($i=0;$i<$max;$i++){ getSequenceArySub($arr,$count,$min,$i,$arrRet,$return); } } return $return; } function getSequenceArySub($arr,$count,$min,$i,$arrRet=array(),& $return){ if(empty($arr) || empty($count)) return false; if(1==$min){ $arrRet[--$min] = $arr[$i]; $return[] = $arrRet; }else{ $arrRet[--$min] = $arr[$i]; for($j = $i+1;$j<($count);$j++){ getSequenceArySub($arr,$count,$min,$j,$arrRet,$return); } } } print_r(getSequenceAry(array(1,2,3,4,5),1)); print_r(getSequenceAry(array(1,2,3,4,5),2)); print_r(getSequenceAry(array(1,2,3,4,5),3)); print_r(getSequenceAry(array(1,2,3,4,5),4)); print_r(getSequenceAry(array(1,2,3,4,5),5)); |
结果:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 |
Array ( [0] => Array ( [0] => 1 ) [1] => Array ( [0] => 2 ) [2] => Array ( [0] => 3 ) [3] => Array ( [0] => 4 ) [4] => Array ( [0] => 5 ) ) Array ( [0] => Array ( [1] => 1 [0] => 2 ) [1] => Array ( [1] => 1 [0] => 3 ) [2] => Array ( [1] => 1 [0] => 4 ) [3] => Array ( [1] => 1 [0] => 5 ) [4] => Array ( [1] => 2 [0] => 3 ) [5] => Array ( [1] => 2 [0] => 4 ) [6] => Array ( [1] => 2 [0] => 5 ) [7] => Array ( [1] => 3 [0] => 4 ) [8] => Array ( [1] => 3 [0] => 5 ) [9] => Array ( [1] => 4 [0] => 5 ) ) Array ( [0] => Array ( [2] => 1 [1] => 2 [0] => 3 ) [1] => Array ( [2] => 1 [1] => 2 [0] => 4 ) [2] => Array ( [2] => 1 [1] => 2 [0] => 5 ) [3] => Array ( [2] => 1 [1] => 3 [0] => 4 ) [4] => Array ( [2] => 1 [1] => 3 [0] => 5 ) [5] => Array ( [2] => 1 [1] => 4 [0] => 5 ) [6] => Array ( [2] => 2 [1] => 3 [0] => 4 ) [7] => Array ( [2] => 2 [1] => 3 [0] => 5 ) [8] => Array ( [2] => 2 [1] => 4 [0] => 5 ) [9] => Array ( [2] => 3 [1] => 4 [0] => 5 ) ) Array ( [0] => Array ( [3] => 1 [2] => 2 [1] => 3 [0] => 4 ) [1] => Array ( [3] => 1 [2] => 2 [1] => 3 [0] => 5 ) [2] => Array ( [3] => 1 [2] => 2 [1] => 4 [0] => 5 ) [3] => Array ( [3] => 1 [2] => 3 [1] => 4 [0] => 5 ) [4] => Array ( [3] => 2 [2] => 3 [1] => 4 [0] => 5 ) ) Array ( [0] => Array ( [4] => 1 [3] => 2 [2] => 3 [1] => 4 [0] => 5 ) ) |
2、穷举排列组合的函数
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 |
<?php function getSequenceAry($arr) { if (count($arr) == 1) { return array($arr); } $arrRet = array(); foreach ($arr as $k => $v) { $arr2 = $arr; unset($arr2[$k]); $arrOrderList = getSequenceAry($arr2); foreach ($arrOrderList as $order) { array_unshift($order, $v); $arrRet[] = $order; } } return $arrRet; } function getSequenceStr($arr) { if (count($arr) == 1) { return $arr; } $arrRet = array(); foreach ($arr as $k => $v) { $arr2 = $arr; unset($arr2[$k]); $arrOrderList = getSequenceStr($arr2); foreach ($arrOrderList as $order) { $arrRet[] = $v . $order; } } return $arrRet; } print_r(getSequenceAry(array(1,2,3))); print_r(getSequenceStr(array(1,2,3))); ------------------ output ------------------ Array ( [0] => Array ( [0] => 1 [1] => 2 [2] => 3 ) [1] => Array ( [0] => 1 [1] => 3 [2] => 2 ) [2] => Array ( [0] => 2 [1] => 1 [2] => 3 ) [3] => Array ( [0] => 2 [1] => 3 [2] => 1 ) [4] => Array ( [0] => 3 [1] => 1 [2] => 2 ) [5] => Array ( [0] => 3 [1] => 2 [2] => 1 ) ) Array ( [0] => 123 [1] => 132 [2] => 213 [3] => 231 [4] => 312 [5] => 321 ) |
穷举排列组合的函数
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2018年07月05日 上午 9:03 爱就爱啦 | 引用 | #41
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