Reverts indentation to 2 spaces.

Author: kelvinlauKL

Stack/Stack.swift

@@ -3,34 +3,34 @@
  Push and pop are O(1) operations.
  */
 public struct Stack<T> {
-    fileprivate var array = [T]()
-    
-    public var isEmpty: Bool {
-        return array.isEmpty
-    }
-    
-    public var count: Int {
-        return array.count
-    }
-    
-    public mutating func push(_ element: T) {
-        array.append(element)
-    }
-    
-    public mutating func pop() -> T? {
-        return array.popLast()
-    }
-    
-    public var top: T? {
-        return array.last
-    }
+  fileprivate var array = [T]()
+  
+  public var isEmpty: Bool {
+    return array.isEmpty
+  }
+  
+  public var count: Int {
+    return array.count
+  }
+  
+  public mutating func push(_ element: T) {
+    array.append(element)
+  }
+  
+  public mutating func pop() -> T? {
+    return array.popLast()
+  }
+  
+  public var top: T? {
+    return array.last
+  }
 }
 
 extension Stack: Sequence {
-    public func makeIterator() -> AnyIterator<T> {
-        var curr = self
-        return AnyIterator {
-            return curr.pop()
-        }
+  public func makeIterator() -> AnyIterator<T> {
+    var curr = self
+    return AnyIterator {
+      return curr.pop()
     }
+  }
 }