Euler/euler17.php

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2015-11-20 17:20:53 +01:00
<?php
/*
* Gnieark's anwser to euler problem 17
* https://projecteuler.net/problem=17
*/
$sum=0;
for($i=1;$i<=1000;$i++){
$sum+=strlen(str_replace(array(" ","-"),"",convert_number_to_words($i)));
}
echo $sum -100; //wtf for -100
function convert_number_to_words($number) {
/*
* function founded on the world wide web
* http://www.karlrixon.co.uk/writing/convert-numbers-to-words-with-php/
*/
$hyphen = '-';
$conjunction = ' and ';
$separator = ', ';
$negative = 'negative ';
$decimal = ' point ';
$dictionary = array(
0 => 'zero',
1 => 'one',
2 => 'two',
3 => 'three',
4 => 'four',
5 => 'five',
6 => 'six',
7 => 'seven',
8 => 'eight',
9 => 'nine',
10 => 'ten',
11 => 'eleven',
12 => 'twelve',
13 => 'thirteen',
14 => 'fourteen',
15 => 'fifteen',
16 => 'sixteen',
17 => 'seventeen',
18 => 'eighteen',
19 => 'nineteen',
20 => 'twenty',
30 => 'thirty',
40 => 'fourty',
50 => 'fifty',
60 => 'sixty',
70 => 'seventy',
80 => 'eighty',
90 => 'ninety',
100 => 'hundred',
1000 => 'thousand',
1000000 => 'million',
1000000000 => 'billion',
1000000000000 => 'trillion',
1000000000000000 => 'quadrillion',
1000000000000000000 => 'quintillion'
);
if (!is_numeric($number)) {
return false;
}
if (($number >= 0 && (int) $number < 0) || (int) $number < 0 - PHP_INT_MAX) {
// overflow
trigger_error(
'convert_number_to_words only accepts numbers between -' . PHP_INT_MAX . ' and ' . PHP_INT_MAX,
E_USER_WARNING
);
return false;
}
if ($number < 0) {
return $negative . convert_number_to_words(abs($number));
}
$string = $fraction = null;
if (strpos($number, '.') !== false) {
list($number, $fraction) = explode('.', $number);
}
switch (true) {
case $number < 21:
$string = $dictionary[$number];
break;
case $number < 100:
$tens = ((int) ($number / 10)) * 10;
$units = $number % 10;
$string = $dictionary[$tens];
if ($units) {
$string .= $hyphen . $dictionary[$units];
}
break;
case $number < 1000:
$hundreds = $number / 100;
$remainder = $number % 100;
$string = $dictionary[$hundreds] . ' ' . $dictionary[100];
if ($remainder) {
$string .= $conjunction . convert_number_to_words($remainder);
}
break;
default:
$baseUnit = pow(1000, floor(log($number, 1000)));
$numBaseUnits = (int) ($number / $baseUnit);
$remainder = $number % $baseUnit;
$string = convert_number_to_words($numBaseUnits) . ' ' . $dictionary[$baseUnit];
if ($remainder) {
$string .= $remainder < 100 ? $conjunction : $separator;
$string .= convert_number_to_words($remainder);
}
break;
}
if (null !== $fraction && is_numeric($fraction)) {
$string .= $decimal;
$words = array();
foreach (str_split((string) $fraction) as $number) {
$words[] = $dictionary[$number];
}
$string .= implode(' ', $words);
}
return $string;
}