diff --git a/C++/chapSorting.tex b/C++/chapSorting.tex
index a1192eb5..0a0ea2a1 100644
--- a/C++/chapSorting.tex
+++ b/C++/chapSorting.tex
@@ -97,7 +97,7 @@ \subsubsection{分析}
 \subsubsection{代码}
 \begin{Code}
 //LeetCode, Merge k Sorted Lists
-// 时间复杂度O(n1+n2+...)，空间复杂度O(1)
+// 时间复杂度O((n1+n2+...)*K)，空间复杂度O(1)  -- 可利用分治思想，时间复杂度是O(N*logK),空间复杂度是O(K).
 class Solution {
 public:
     ListNode *mergeKLists(vector<ListNode *> &lists) {