diff --git a/NineChess/src/aithread.cpp b/NineChess/src/aithread.cpp
index 7d7251b6..7d629568 100644
--- a/NineChess/src/aithread.cpp
+++ b/NineChess/src/aithread.cpp
@@ -1,7 +1,12 @@
 #include <QDebug>
 #include "aithread.h"
 
-AiThread::AiThread(int id, QObject *parent) : QThread(parent), waiting_(false), aiDepth(2), aiTime(120)
+AiThread::AiThread(int id, QObject *parent) : 
+    QThread(parent), 
+    chess_(nullptr),
+    waiting_(false), 
+    aiDepth(2), 
+    aiTime(120)
 {
     this->id = id;
 
@@ -25,6 +30,7 @@ AiThread::~AiThread()
 void AiThread::setAi(const NineChess &chess)
 {
     mutex.lock();
+
     this->chess_ = &chess;
     ai_ab.setChess(*(this->chess_));
 
diff --git a/NineChess/src/config.h b/NineChess/src/config.h
index 875543f3..d3aa117a 100644
--- a/NineChess/src/config.h
+++ b/NineChess/src/config.h
@@ -3,7 +3,7 @@
 
 //#define DEBUG
 
-#define RANDOM_MOVE
+//#define RANDOM_MOVE
 
 #define DEAL_WITH_HORIZON_EFFECT