function generate_gives_to($group_list, $attempt = 0)
{
$recipients = [];
$givesto = [];
$attempt += 1;
foreach ($group_list as $k1 => $group) {
$possible_recipients = array_merge(array_slice($group_list, 0, $k1), array_slice($group_list, $k1 + 1));
$possible_recipients = array_diff(flatten($possible_recipients), $recipients);
foreach ($group as $k2 => $person) {
if (empty($possible_recipients)) {
if ($attempt < 10) {
return generate_gives_to($group_list, $attempt);
} else {
echo " - INCOMPLETE SOLUTION - ";
}
}
$k = array_rand($possible_recipients);
$givesto[$person] = $possible_recipients[$k];
$recipients[] = $possible_recipients[$k];
unset($possible_recipients[$k]);
}
}
fancy_print($givesto);
return $givesto;
}
function generate_gives_to($group_list, $fancy_print = true, $attempt = 0)
{
$recipients = [];
$givesto = [];
$attempt += 1;
foreach ($group_list as $k1 => $group) {
$possible_recipients = array_merge(array_slice($group_list, 0, $k1), array_slice($group_list, $k1 + 1));
$possible_recipients = array_diff(flatten($possible_recipients), $recipients);
foreach ($group as $k2 => $person) {
if (empty($possible_recipients)) {
if ($attempt < 10) {
return generate_gives_to($group_list, $fancy_print, $attempt);
} else {
return false;
}
}
$k = array_rand($possible_recipients);
$givesto[trim($person)] = trim($possible_recipients[$k]);
$recipients[] = $possible_recipients[$k];
unset($possible_recipients[$k]);
}
}
//echo fancy_print($givesto);
//return $givesto;
return $fancy_print ? fancy_print($givesto) : json_encode($givesto);
}
<?php include 'givesto.php'; $group_list = [['John', 'Paul', 'George', 'Ringo'], ['Elmo', 'Oscar', 'Big Bird', 'Bert'], ['Larry', 'Curly', 'Moe']]; generate_gives_to($group_list);
<?php
include 'givesto.php';
$groups = explode("\n", $_GET['input']);
$group_list = [];
foreach ($groups as $k => $group_string) {
$group_list[$k] = explode(",", $group_string);
}
if (is_null($group_list)) {
// bad input
http_response_code(400);
exit;
}
$result = generate_gives_to($group_list, false);
if ($result === false) {
http_response_code(400);
echo "Incomplete Solution - Try adding another group";
exit;
}
http_response_code(200);
print_r($result);