From fc8635016cb649a151680ff97bae6de0971fd888 Mon Sep 17 00:00:00 2001
From: cinita <cinita.lv@gmail.com>
Date: Thu, 10 Jan 2019 00:43:52 +0800
Subject: [PATCH] update quick sort

---
 java/12_sorts/QuickSort.java | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/java/12_sorts/QuickSort.java b/java/12_sorts/QuickSort.java
index d2523c2..0813657 100644
--- a/java/12_sorts/QuickSort.java
+++ b/java/12_sorts/QuickSort.java
@@ -24,10 +24,13 @@ public class QuickSort {
     int i = p;
     for(int j = p; j < r; ++j) {
       if (a[j] < pivot) {
-        int tmp = a[i];
-        a[i] = a[j];
-        a[j] = tmp;
-        ++i;
+        if (i == j) {
+          ++i;
+        } else {
+          int tmp = a[i];
+          a[i++] = a[j];
+          a[j] = tmp;
+        }
       }
     }