日期:2014-05-17 浏览次数:20684 次
<?php $str=array(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33); for($i=0;$i<28;$i++){ for($j=$i+1;$j<33;$j++){ for($k=$j+1;$k<33;$k++){ for($l=$j+1;$l<33;$l++){ for($m=$l+1;$m<33;$m++){ for($n=$m+1;$n<33;$n++){ echo "$str[i]|$str[j]|$str[k]|$str[l]|$str[m]|$str[n]|<br>";//显示效果,本想写入TXT文档在传如数据库. } } } } } } ?>
$a = range(1, 33); $ar = combination($a, 6); //求组合高效率的10移动法 function combination($numArr,$combineLen) { $numCt = count($numArr); if($combineLen > $numCt) return; $bin = str_pad('',$combineLen,'1'); $bin = str_pad($bin,$numCt,'0',STR_PAD_RIGHT); $find = $bin; $rs[] = implode(' ',array_slice($numArr,0,$combineLen)); $j = 1; while(strrev($find) != $bin) { $k = explode('10',$find,2); $find = $find{0} === '0' ? strrev($k[0]).'01'.$k[1] : $k[0].'01'.$k[1]; for($i=0;$i<$numCt;$i++) $rs[$j] .= $find[$i] ? $numArr[$i] . " " : ''; $j++; } return $rs; }
------解决方案--------------------
[User:root Time:21:21:46 Path:/home/liangdong/php]$ php permutation.php Total time used : 9738642ms [User:root Time:21:21:56 Path:/home/liangdong/php]$ cat permutation.php <?php $beg_time = microtime(true); $beg_time *= 1000 * 1000; $table = range(1, 33); $temp = array(); $fp = null; function _get_permutations($index, $num) { global $temp; global $total; global $table; global $fp; if ($num == $total) { global $perms; fwrite($fp, json_encode($temp) . PHP_EOL); return; } for ($ndx = $index; 33 - $ndx + $num >= $total; ++ $ndx) { $temp[$num] = $table[$ndx]; _get_permutations($ndx + 1, $num + 1); } } function get_permutations($n = 6) { global $total; global $perms; global $fp; if ($n <= 0 && $n > 33) { return false; } $total = $n; $fp = fopen("data.txt", "w"); _get_permutations(0, 0); fclose($fp); return true; } get_permutations(); $end_time = microtime(true); $end_time *= 1000 * 1000; echo "Total time used : " . ($end_time - $beg_time) . "ms" . PHP_EOL; ?>