function permutations(array $elements)
{
if (count($elements) <= 1) {
(yield $elements);
} else {
foreach (permutations(array_slice($elements, 1)) as $permutation) {
foreach (range(0, count($elements) - 1) as $i) {
(yield array_merge(array_slice($permutation, 0, $i), [$elements[0]], array_slice($permutation, $i)));
}
}
}
}
function resetAndAddMe()
{
global $permutations;
global $happiness;
global $names;
$permutations = array();
foreach ($names as $name) {
$happiness[$name]['Anton'] = 0;
$happiness['Anton'][$name] = 0;
}
$names[] = 'Anton';
permutations($names);
}
function permutations($num, $max)
{
if ($num == 1) {
return [[$max]];
}
$r = [];
for ($i = 0; $i <= $max; $i++) {
foreach (permutations($num - 1, $max - $i) as $j) {
$r[] = array_merge($j, [$i]);
}
}
return $r;
}
function permutations($items, $perms = array())
{
global $permutations;
if (empty($items)) {
$permutations[] = join(',', $perms);
} else {
for ($i = count($items) - 1; $i >= 0; --$i) {
$newitems = $items;
$newperms = $perms;
list($foo) = array_splice($newitems, $i, 1);
array_unshift($newperms, $foo);
permutations($newitems, $newperms);
}
}
}
function permutations($items, $perms = [])
{
if (empty($items)) {
$return = array($perms);
} else {
$return = array();
for ($i = count($items) - 1; $i >= 0; --$i) {
$newitems = $items;
$newperms = $perms;
list($foo) = array_splice($newitems, $i, 1);
array_unshift($newperms, $foo);
$return = array_merge($return, permutations($newitems, $newperms));
}
}
return $return;
}
/**
* Calculatie the most happiness
*
* @param array $map
* @return int
*/
function happiness(array $map)
{
$people = array_keys($map);
$currentPerson = $people[0];
$scores = [];
// Build a array with all possible options
foreach (permutations(array_slice($people, 1)) as $set) {
// Add the current person to the set
$set[] = $currentPerson;
$left = $currentPerson;
$key = implode('.', $set);
$scores[$key] = 0;
// Build a scores chart
foreach ($set as $right) {
$scores[$key] += $map[$left][$right];
$scores[$key] += $map[$right][$left];
$left = $right;
}
}
return max($scores);
}
function permutations(array $array, $key = 0, $limit = 8)
{
static $result;
$count = count($array);
try {
if ($count > $limit) {
throw new LengthException(sprintf('Error!: Unable to generate permutations with more than %d values', $limit));
}
if ($key == $count) {
$result[] = $array;
} else {
for ($i = $key; $i < $count; $i++) {
list($array[$key], $array[$i]) = array($array[$i], $array[$key]);
permutations($array, $key + 1);
}
}
return $result;
} catch (LengthException $e) {
echo $e->getMessage();
}
}
if ($value2[0] == $value && $value2[2] == $sitRight) {
$totHappiness += $value2[1];
}
}
}
return $totHappiness;
}
$gainLoseArr = [];
$myfile = fopen("day13_input.txt", "r") or die("Unable to open file!");
while (!feof($myfile)) {
$line = trim(fgets($myfile));
$lineArr = explode(" ", $line);
if ($lineArr[2] == "lose") {
$gainLoseArr[] = [$lineArr[0], "-" . $lineArr[3], trim($lineArr[10], ".")];
} else {
$gainLoseArr[] = [$lineArr[0], $lineArr[3], trim($lineArr[10], ".")];
}
}
fclose($myfile);
$nameArray = [];
foreach ($gainLoseArr as $value) {
if (!in_array($value[0], $nameArray)) {
$nameArray[] = $value[0];
}
}
$possibleSeatArr = permutations(array_values($nameArray));
$totHappinessArr = [];
foreach ($possibleSeatArr as $key => $value) {
$totHappinessArr[] = calcTable($gainLoseArr, $value);
}
echo max($totHappinessArr);
foreach ($distances as $key => $value) {
if (in_array($currCity, $value) && in_array($nextCity, $value)) {
$thisDistance += $value[2];
break;
}
}
}
$totDistances[] = $thisDistance;
}
return max($totDistances);
}
$cities = [];
$distances = [];
$myfile = fopen("day9_input.txt", "r") or die("Unable to open file!");
while (!feof($myfile)) {
$line = trim(fgets($myfile));
$lineArr = explode(" ", $line);
if (!in_array($lineArr[0], $cities)) {
$cities[] = $lineArr[0];
}
if (!in_array($lineArr[2], $cities)) {
$cities[] = $lineArr[2];
}
$distances[] = [$lineArr[0], $lineArr[2], $lineArr[4]];
}
fclose($myfile);
$permArr = permutations(array_values($cities));
if (!in_array($cities, $permArr)) {
$permArr[] = $cities;
}
echo calcShortest($permArr, $distances);
function permutations($first = '', $arr, &$results = array())
{
$len = count($arr);
if ($len == 1) {
$results[] = $first . "," . $arr[0];
} else {
for ($i = 0; $i < $len; $i++) {
$tmp = $arr[0];
$arr[0] = $arr[$i];
$arr[$i] = $tmp;
permutations($first . "," . $arr[0], array_slice($arr, 1), $results);
}
}
}