update code format

kotlin/08_stack/StackBasedOnLinkedList.kt

@@ -5,32 +5,32 @@
  */
 
 class StackBasedOnLinkedList {
+    
+    private var top: Node? = null
 
-	private var top: Node? = null
+    fun push(value: Int) {
+        val newNode = Node(value, null)
+        // 不管 top 是不是 null，都可以这么写
+        newNode.next = top
+        top = newNode
+    }
 
-	fun push(value: Int) {
+    fun pop(): Int {
-		val newNode = Node(value, null)
+        if (top == null) return -1
-		// 不管 top 是不是 null，都可以这么写
+        val node = top
-		newNode.next = top
+        top = top!!.next
-		top = newNode
+        return node!!.data
-	}
+    }
 
-	fun pop(): Int {
+    fun printAll() {
-		if (top == null) return -1
+        var p = top
-		val node = top
+        while (p != null) {
-		top = top!!.next
+            print("${p.data} ")
-		return node!!.data
+            p = p.next
-	}
+        }
-
+        println()
-	fun printAll() {
+    }
-		var p = top
-		while(p != null) {
-			print("${p.data} ")
-			p = p.next
-		}
-		println()
-	}
 
     class Node(var data: Int, var next: Node?)
-    
+
 }