function doManyTimes($input, $times)
{
echo '00: ' . $input . ' - ' . strlen($input) . '<br>';
foreach (range(1, $times) as $i) {
$input = lookAndSay($input);
echo ($i < 10 ? '0' . $i : $i) . ': ' . substr($input, -100) . (strlen($input) > 100 ? '…' : '') . ' - ' . strlen($input) . '<br>';
}
if ($i === $times) {
echo '<h4>string length: ' . strlen($input) . '</h4>';
}
}
exit("Unable to load input file");
}
function lookAndSay($number)
{
$lastDigit = null;
$digitCount = 1;
$output = '';
for ($d = 0; $d < strlen($number); $d++) {
$digit = $number[$d];
if ($digit == $lastDigit) {
$digitCount++;
continue;
}
if (!is_null($lastDigit)) {
$output .= $digitCount . $lastDigit;
}
$lastDigit = $digit;
$digitCount = 1;
}
$output .= $digitCount . $lastDigit;
return $output;
}
for ($c = 0; $c < 40; $c++) {
$number = lookAndSay($number);
}
$after40 = strlen($number);
for ($c = 0; $c < 10; $c++) {
$number = lookAndSay($number);
}
$after50 = strlen($number);
print "\nPart 1: {$after40}\nPart 2: {$after50}\n";
<?php
ini_set('memory_limit', '1024M');
$input = '1113122113';
function lookAndSay($input, $times)
{
for ($i = 0; $i < $times; $i++) {
$input = str_split($input);
$output = '';
$lastValue = '';
foreach ($input as $key => $value) {
if ($value === $lastValue) {
continue;
}
$count = 0;
for ($j = $key; $j < count($input); $j++) {
if ($input[$j] !== $value) {
break;
}
$count++;
}
$output .= $count . $value;
$lastValue = $value;
}
$input = $output;
}
return $input;
}
echo 'Length of result after 40 passes is ' . strlen(lookAndSay($input, 40)) . PHP_EOL;
echo 'Length of result after 50 passes is ' . strlen(lookAndSay($input, 50)) . PHP_EOL;
<?php
function lookAndSay($str)
{
return preg_replace_callback('#(.)\\1*#', function ($matches) {
return strlen($matches[0]) . $matches[1];
}, $str);
}
$num = "1";
foreach (range(1, 10) as $i) {
echo $num . "<br/>";
$num = lookAndSay($num);
}
<?php
function lookAndSay($s)
{
$r = '';
// возвращаемое значение
$m = $s[0];
// подсчитываемый символ
$n = 1;
// количество обнаруженных $m}
for ($i = 1, $j = strlen($s); $i < $j; $i++) {
if ($s[$i] == $m) {
$n++;
} else {
$r .= $n . $m;
$m = $s[$i];
$n = 1;
}
}
return $r . $n . $m;
}
for ($i = 0, $s = 1; $i < 10; $i++) {
$s = lookAndSay($s);
print "{$s}<br>";
}
<?php
$say = "1113122113";
for ($x = 0; $x < 50; $x++) {
$say = lookAndSay($say);
}
echo strlen($say) . "\n";
function lookAndSay($str)
{
$prevDigit = -1;
$runs = 0;
$out = '';
for ($x = 0; $x < strlen($str); $x++) {
$digit = substr($str, $x, 1);
if ($prevDigit == -1) {
$runs++;
$prevDigit = $digit;
continue;
}
if ($prevDigit == $digit) {
$runs++;
} else {
$out .= $runs . $prevDigit;
$runs = 1;
}
$prevDigit = $digit;
}
$out .= $runs . $prevDigit;
return $out;
}
<?php
include 'header.php';
for ($sequence = SEQUENCE, $i = 0, $loops = 40; $i < $loops; $i++) {
$sequence = lookAndSay($sequence);
}
echo strlen($sequence), PHP_EOL;
$inputLen = strlen($input);
$current = '';
$howMany = 1;
$output = '';
for ($i = 0; $i < $inputLen; $i++) {
if ($current === $input[$i]) {
$howMany++;
} else {
if (!empty($current)) {
$output .= strval($howMany) . $current;
}
$current = $input[$i];
$howMany = 1;
}
}
$output .= strval($howMany) . $current;
return $output;
}
$input = '1113122113';
$nbRotationPart1 = 40;
$nbRotationPart2 = 50;
for ($i = 0; $i < $nbRotationPart2; $i++) {
$input = lookAndSay($input);
if ($i === $nbRotationPart1 - 1) {
$outputPart1 = $input;
}
}
print 'Part1: ' . strlen($outputPart1);
print PHP_EOL;
print 'Part2: ' . strlen($input);
print PHP_EOL;
