Added changed by opened discussions

Author: PavelKochenda

Queue/Queue-Optimized.swift

@@ -47,12 +47,10 @@ public struct Queue<T> {
 }
 
 extension Array {
-    
     subscript(guarded idx: Int) -> Element? {
         guard (startIndex..<endIndex).contains(idx) else {
             return nil
         }
         return self[idx]
     }
-    
 }