20171119 利用周末优化了一下代码。这次完全默写了出来。感觉好多了

  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   $length) { if ($isStartNode) { $costs[$name] = $length; } else {$costs[$name] = INF; }$costs += getNodeCost($graphs,$name); } return $costs; }$costs = getNodeCost($graphs, 'start', true); function getNodeParents($graphs, $nodeName = 'start',$isStartNode = false) { if (empty($graphs)) { return []; }$parents = []; foreach ($graphs[$nodeName] as $name =>$length) { if ($isStartNode) {$parents[$name] =$nodeName; } else { $parents[$name] = null; } $parents += getNodeParents($graphs, $name); } return$parents; } $parents = getNodeParents($graphs, 'start', true); function findLowestCostNode($costs,$processed) { $lowestNodeLength = INF;$lowestNOdeName = ''; foreach ($costs as$name => $length) { if ($length < $lowestNodeLength && !in_array($name, $processed)) {$lowestNodeLength = $length;$lowestNOdeName = $name; } } return$lowestNOdeName; } $nodeName = findLowestCostNode($costs, $processed); while ($nodeName) { $currentNodeCost =$costs[$nodeName]; foreach ($graphs[$nodeName] as$name => $length) { if ($currentNodeCost + $length <$costs[$name]) {$costs[$name] =$currentNodeCost + $length;$parents[$name] =$nodeName; } } $processed[] =$nodeName; $nodeName = findLowestCostNode($costs, $processed); } var_dump($costs); var_dump(\$parents);