这不是家庭作业:在工作时遇到了这个场景PHP字符串差异和动态限制
给定一串n
单词,如何在不改变单词序列的情况下将它们分配到m
组中?
Example 1:
String: "My name is SparKot"
Groups: 2 (string is split in to two strings)
Possible groups will be:
('My', 'name is SparKot'),
('My name', 'is SparKot'),
('My name is', 'SparKot')
与相同的字符串
Example 2:
String: "My name is SparKot"
Groups: 3 (string will be split in to three strings)
Possible groups will be:
('My', 'name', 'is SparKot'),
('My', 'name is', 'SparKot'),
('My name', 'is', 'SparKot')
我的PHP函数()没有方向(它应该返回多维组):
function get_possible_groups ($orgWords, $groupCount, &$status) {
$words = explode (' ', $orgWords);
$wordCount = count($words);
if ($wordCount < $groupCount) {
$status = -1;
return;
} else if ($wordCount === $groupCount) {
$status = 0;
return (array_chunk($words, 1));
}
for ($idx =0; $idx < $wordCount; $idx) {
for ($jdx =0; $jdx < $groupCount; $jdx++) {
}
}
// append all arrays to form multidimension array
// return groupings[][] array
}
$status =0;
$groupings = get_possible_groups('My name is SparKot', 4, $status);
var_dump($groupings);
对于上面的示例2函数应该返回:
$groupings = array (
array ('My', 'name', 'is SparKot'),
array ('My', 'name is', 'SparKot'),
array ('My name', 'is', 'SparKot'));
对于解决这个问题的任何提示都将不胜感激。
进步:
- 案例:当
wordCount = groupCount
[solved]
好吧,我花了不少时间,但我想我已经把这个弄对了。老实说,我真的很自豪,因为我通常不太擅长算法。不管怎样,我们开始吧:
function getPossibleGroups($string, $groups) {
$words = explode(' ', $string);
$wordCount = count($words);
if ($groups === 1) {
return array(array($string));
} elseif ($groups > $wordCount) {
return null;
} elseif ($groups === $wordCount) {
return array($words);
}
$results = array();
// We get every possible result for the first group
for ($i = 1; $i <= $wordCount - $groups + 1; $i++) {
$firstGroup = implode(' ', array_slice($words, 0, $i));
// Recursively get all posible results for the other groups
$otherGroups = getPossibleGroups(implode(' ', array_slice($words, $i)), $groups - 1);
// Merge both things
$allGroups = array_map(function($v) use ($firstGroup) {
return array_merge(array($firstGroup), $v);
}, $otherGroups);
// Add that to the results variable
$results = array_merge($results, $allGroups);
}
return $results;
}