Restructuring

solutions/ProjectEuler/035/desc.yml

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+title: How many circular primes are there below one million?
+url: http://projecteuler.net/problem=35
+
+desc: |
+  The number, 197, is called a circular prime because all rotations of the digits: 197, 971, and 719, are themselves prime.
+  There are thirteen such primes below 100: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, and 97.
+  How many circular primes are there below one million?
+solution: Bruteforce
+solutions:
+
+

solutions/ProjectEuler/035/solve.php

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+<?php
+
+function is_prime($prime) {  
+    if($prime < 1)
+        return false;
+
+	if($prime == 1) 
+		return true;
+	if($prime == 2)
+		return true;
+    $sqrt = sqrt($prime);
+    for ($i = 3; $i <= $sqrt; $i+=2){
+        if ($prime%$i == 0) return false; 
+    } 
+    return true; 
+}
+
+if (($handle = fopen("primes1000000.txt", "r")) !== FALSE) {
+    while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
+        if ($data[1] >= 1000000)
+            break;
+        //If there's an even digit (or a 5) we can instantly exclude it as when rotated it will not not be a prime.
+        if (
+            strpos((string) $data[1], "0") !== false ||
+            strpos((string) $data[1], "2") !== false ||
+            strpos((string) $data[1], "4") !== false ||
+            strpos((string) $data[1], "5") !== false ||
+            strpos((string) $data[1], "6") !== false ||
+            strpos((string) $data[1], "8") !== false
+        ) {
+
+            continue;
+        }
+        $primes[] = (int) $data[1];
+    }
+    fclose($handle);
+}
+echo "File read\n";
+
+$count = 1+1; //2 and 5 are primes but not included
+foreach($primes as $prime) 
+{
+        //echo "Now testing $prime\n";
+        $newprime = $prime;
+        for($rotate = 1; $rotate < strlen($prime); $rotate++)
+        {
+            $newprime = substr($newprime, -1, 1).substr($newprime, 0, -1);
+            //echo "New prime: $newprime\n";
+            if(!in_array($newprime, $primes))
+            {
+                continue 2;
+            }
+
+        }
+        $count++;
+        echo $prime.PHP_EOL;
+
+
+}
+
+echo "Total: $count\n";