2015-11-15 00:06:08 +01:00
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<?php
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/*
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* Gnieark's anwser to euler problem 3
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* https://projecteuler.net/problem=3
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*/
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2015-11-15 22:53:49 +01:00
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require_once("_functions.php");
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2015-11-15 00:06:08 +01:00
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echo largestPrimeFactorOf(600851475143);
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function largestPrimeFactorOf($number){
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2015-11-15 22:53:49 +01:00
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$right=$number;
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$i=1;
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$prFact=1;
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while(getPrimeNumber($i)<=$right){
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if(fmod($right,getPrimeNumber($i))==0){
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$prFact=getPrimeNumber($i);
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$right=$right/$prFact;
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}
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$i++;
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2015-11-15 00:06:08 +01:00
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}
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2015-11-15 22:53:49 +01:00
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return $prFact;
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}
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