Common Denominators

5-kyu/Common Denominators/src/convertFrac.php

@@ -0,0 +1,47 @@
+<?php
+function convertFrac($lst)
+{
+    $gcd_item = [];
+    foreach ($lst as $v) {
+        //     if(isset($v[1]))
+        //       $gcd_item[] = $v[1];
+        if (gcd($v[0], $v[1]) == 1) {
+            $gcd_item[] = $v[1];
+        } else {
+            $gcd_item[] = $v[1] /  gcd($v[0], $v[1]);
+        }
+    }
+    if (count($gcd_item) > 0) {
+        $lcm = findlcm($gcd_item, count($gcd_item));
+    }
+    // var_dump($lst, $gcd_item, '$lcm = ' .  $lcm);
+    //   var_dump($lcm);
+
+    $result  = '';
+
+    foreach ($lst as $v) {
+        $result =  $result . '(' . (($lcm / $v[1]) * $v[0]) . ',' . ($lcm) . ')';
+    }
+    return $result;
+}
+
+function gcd($a, $b)
+{
+    return ($a % $b) ? gcd($b, $a % $b) : $b;
+}
+// https://www.geeksforgeeks.org/lcm-of-given-array-elements/
+// Returns LCM of array elements 
+function findlcm($arr, $n)
+{
+
+    // Initialize result 
+    $ans = $arr[0];
+
+    // ans contains LCM of  
+    // arr[0], ..arr[i] 
+    // after i'th iteration, 
+    for ($i = 1; $i < $n; $i++)
+        $ans = ((($arr[$i] * $ans)) / (gcd($arr[$i], $ans)));
+
+    return $ans;
+}

5-kyu/Common Denominators/test/CommonDenominatorTest.php

@@ -0,0 +1,22 @@
+<?php
+
+use PHPUnit\Framework\TestCase;
+
+class CommonDenominatorTest extends TestCase
+{
+    private function revTest($actual, $expected)
+    {
+        $this->assertEquals($expected, $actual);
+    }
+    public function testBasics()
+    {
+        $lst = [[1, 2], [1, 3], [1, 4]];
+        $this->revTest(convertFrac($lst), "(6,12)(4,12)(3,12)");
+        $lst = [[69, 130], [87, 1310], [3, 4]];
+        $this->revTest(convertFrac($lst), "(18078,34060)(2262,34060)(25545,34060)");
+        $lst = [];
+        $this->revTest(convertFrac($lst), "");
+        $lst = [[77, 130], [84, 131], [3, 4]];
+        $this->revTest(convertFrac($lst), "(20174,34060)(21840,34060)(25545,34060)");
+    }
+}

phpunit.xml

@@ -38,5 +38,9 @@
         <file>7-kyu/Exes and Ohs/src/XO.php</file>
         <directory>7-kyu/Exes and Ohs/test</directory>
     </testsuite>
+    <testsuite name="5-kyu-Common-Denominators">
+        <file>5-kyu/Common Denominators/src/convertFrac.php</file>
+        <directory>5-kyu/Common Denominators/test</directory>
+    </testsuite>
   </testsuites>
 </phpunit>