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✨ Finit le jour 8 et le début du 9

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This commit is contained in:
Clement Desmidt
2021-12-09 17:31:46 +01:00
parent f1899b0640
commit c290b5fee6
3 changed files with 145 additions and 0 deletions
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15
day_8/part_1.php Normal file
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<?php
$output = array_map(static function ($line) {
return explode('|', $line)[1];
}, explode("\n", file_get_contents('./input.txt')));
echo array_reduce($output, static function($carry, $item) {
$count = 0;
$items = explode(' ', $item);
foreach ($items as $item) {
$count += in_array(strlen($item), [2, 4, 3, 7]) ? 1 : 0;
}
$carry += $count;
return $carry;
});

99
day_8/part_2.php Normal file
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<?php
$entries = explode("\n", file_get_contents('./input.txt'));
$outputs = [];
foreach ($entries as $entry) {
[$uniques, $output] = explode('|', $entry);
$uniques = array_filter(explode(' ', $uniques));
$output = array_filter(explode(' ', $output));
$mapping = [];
while (count($mapping) !== 10) {
foreach ($uniques as $unique) {
$unique = sort_string($unique);
if (in_array($unique, $mapping)) {
continue;
}
switch (strlen($unique)) {
case 2: $mapping[1] = $unique; break;
case 4: $mapping[4] = $unique; break;
case 3: $mapping[7] = $unique; break;
case 7: $mapping[8] = $unique; break;
case 5:
if (array_key_exists(1, $mapping)) {
$segments_1 = str_split($mapping[1]);
if (str_contains($unique, $segments_1[0]) && str_contains($unique, $segments_1[1])) {
$mapping[3] = $unique;
break;
}
}
if (array_key_exists(9, $mapping)) {
$segments_9 = str_split($mapping[9]);
$count = 0;
foreach ($segments_9 as $segment_9) {
if (!str_contains($unique, $segment_9)) {
$count++;
}
}
if ($count === 1) {
$mapping[5] = $unique;
break;
} else {
$mapping[2] = $unique;
break;
}
}
break;
case 6:
if (array_key_exists(1, $mapping)) {
$segments_1 = str_split($mapping[1]);
if (!str_contains($unique, $segments_1[0]) || !str_contains($unique, $segments_1[1])) {
$mapping[6] = $unique;
break;
}
}
if (array_key_exists(4, $mapping)) {
$segments_4 = str_split($mapping[4]);
if (
str_contains($unique, $segments_4[0]) &&
str_contains($unique, $segments_4[1]) &&
str_contains($unique, $segments_4[2]) &&
str_contains($unique, $segments_4[3])
) {
$mapping[9] = $unique;
break;
}
}
if (array_key_exists(6, $mapping) && array_key_exists(9, $mapping)) {
$mapping[0] = $unique;
break;
}
break;
default:
echo 'unknown length : '.strlen($unique);
}
}
}
$number = '';
foreach ($output as $item) {
$item = sort_string($item);
$number .= array_search($item, $mapping);
}
echo sprintf('%u%s', $number, "\n");
$outputs[] = (int) $number;
}
echo array_sum($outputs);
function sort_string(string $string)
{
$string = str_split($string);
sort($string);
return implode($string);
}

31
day_9/part_1.php Normal file
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<?php
$grid = array_map(static function ($row) {
return str_split($row);
}, explode("\n", file_get_contents('./input.txt')));
$low_points = [];
foreach ($grid as $i => $row) {
foreach ($row as $j => $cell) {
$count = 0;
if (!array_key_exists($i - 1, $grid) || $grid[$i - 1][$j] > $cell) {
$count++;
}
if (!array_key_exists($i + 1, $grid) || $grid[$i + 1][$j] > $cell) {
$count++;
}
if (!array_key_exists($j - 1, $row) ||$row[$j - 1] > $cell) {
$count++;
}
if (!array_key_exists($j + 1, $row) || $row[$j + 1] > $cell) {
$count++;
}
if ($count === 4) {
$low_points[] = (int) $cell;
}
}
}
echo array_sum($low_points) + count($low_points);