Binary Search Code added

Author: me-shaon

README.md

@@ -22,8 +22,8 @@
 
 
 - [Searching](./Searching/)
-  - Linear Search
-  - Binary Search
+  - [Linear Search](./Searching/Linear%20Search)
+  - [Binary Search](./Searching/Binary%20Search)
   - Ternary Search
 
 

Searching/Binary Search/binary_search.php

@@ -0,0 +1,35 @@
+<?php
+/* Binary Search implementation in PHP */
+function binarySearch(Array $arr, $item) {
+    $low = 0;
+    $high = count($arr) - 1;
+	$found = false;
+
+	while ($low <= $high) {
+		$mid = $low + ($high - $low) / 2; //Midpoint of the Search Space
+
+		if ($arr[$mid] === $item) { //Found the element
+			$found = true;
+			break;
+		} else {
+			if ($item < $arr[$mid]) { //Need to search in the left half of the search space
+				$high = $mid - 1;
+			} else { //Need to search in the right half of the search space
+				$low = $mid + 1;
+			}
+		}
+	}
+
+	return $found;
+}
+
+
+/************ Testing Binary Search Implementation ***************/
+
+// This list must be sorted. If it is not given as sorted, sort it first, then call the binarySearch method
+$testList = array(0, 1, 2, 8, 13, 17, 19, 32, 42);
+echo binarySearch($testList, 3) ? 'True' : 'False';
+echo PHP_EOL;
+echo binarySearch($testList, 13) ? 'True' : 'False';
+
+?>