Update the book based on the revised second edition (#1014)

* Revised the book

* Update the book with the second revised edition

* Revise base on the manuscript of the first edition

codes/swift/chapter_heap/my_heap.swift

@@ -20,17 +20,17 @@ class MaxHeap {
         }
     }
 
-    /* 获取左子节点索引 */
+    /* 获取左子节点的索引 */
     private func left(i: Int) -> Int {
         2 * i + 1
     }
 
-    /* 获取右子节点索引 */
+    /* 获取右子节点的索引 */
     private func right(i: Int) -> Int {
         2 * i + 2
     }
 
-    /* 获取父节点索引 */
+    /* 获取父节点的索引 */
     private func parent(i: Int) -> Int {
         (i - 1) / 2 // 向下整除
     }