Powershell Version of Binary Search (#15)

* Powershell Version of Binary Search

01_introduction_to_algorithms/PowerShell/01_binary_search/Search-Binary.ps1

@@ -0,0 +1,58 @@
+#Binary Search in Powershell / .net
+#Author ITAdder (Justino Garcia)
+#clear screen after every run.
+clear-host
+
+$mylist = (1,3,5,7,9);
+
+
+function Search-Binary
+{
+    #[CmdletBinding()]
+    #[Alias()]
+    #[OutputType([int])]
+    Param
+    (
+        #  numeric lists 
+        [Parameter(Mandatory=$true,
+                   ValueFromPipelineByPropertyName=$true,
+                   Position=0)]
+        
+        [int[]]$list,
+
+        # $item will then be passed between calls as you reduce your list
+        
+        $item
+    )
+
+    [int] $low = 0;
+    $high = $list.Length -1;
+
+    while ($low -lt $high) {
+
+        $mid = ($low + $high) / 2;
+
+        $guess = $list[$mid];
+
+
+        if ($guess -eq $item) {
+    
+            return $mid;
+        }
+
+        if ($guess -gt $item)
+        {
+            $high = ($mid -1);
+        }
+
+        else{
+
+            $low = $mid + 1
+        }
+          return $null;      
+    }
+        
+
+    }
+
+    Search-Binary -list $mylist -item 2