added naive impletation for project euler problem 87 in php

2017-04-11/ikselven_euler87-foreach.php

@@ -0,0 +1,35 @@
+#!/usr/bin/php
+<?php
+define("MAX", 5*(10**7));
+
+$nextPrime = 2;
+$primes = array($nextPrime);
+while ($nextPrime < sqrt(MAX)) {
+    $nextPrime = gmp_intval(gmp_nextprime($nextPrime));
+    $primes[] = $nextPrime;
+}
+
+$sums = array();
+foreach($primes as $outer) {
+    $fourth = $outer ** 4;
+    if ($fourth >= MAX) {
+        break;
+    }
+    
+    foreach($primes as $middle) {
+        $cube = $fourth + $middle ** 3;
+        if ($cube >= MAX) {
+            break;
+        }
+
+        foreach($primes as $inner) {
+            $sum = $cube + $inner ** 2;
+            if ($sum >= MAX) {
+                break;
+            }
+            $sums[] = $sum;
+        }
+    }
+}
+
+echo "Found ".count(array_unique($sums))." numbers\n";

2017-04-11/ikselven_euler87.php

@@ -0,0 +1,36 @@
+#!/usr/bin/php
+<?php
+define("MAX", 5*(10**7));
+
+$nextPrime = 2;
+$primes = array($nextPrime);
+while ($nextPrime < sqrt(MAX)) {
+    $nextPrime = gmp_intval(gmp_nextprime($nextPrime));
+    $primes[] = $nextPrime;
+}
+
+$sums = array();
+$primeCount = count($primes);
+for($outer = 0; $outer < $primeCount; $outer++) {
+    $fourth = $primes[$outer] ** 4;
+    if ($fourth >= MAX) {
+        break;
+    }
+    
+    for($middle = 0; $middle < $primeCount; $middle++) {
+        $cube = $fourth + $primes[$middle] ** 3;
+        if ($cube >= MAX) {
+            break;
+        }
+
+        for($inner = 0; $inner < $primeCount; $inner++) {
+            $sum = $cube + $primes[$inner] ** 2;
+            if ($sum >= MAX) {
+                break;
+            }
+            $sums[] = $sum;
+        }
+    }
+}
+
+echo "Found ".count(array_unique($sums))." numbers\n";