diff --git a/button.c b/button.c
index 9dcf3a5..233699c 100644
--- a/button.c
+++ b/button.c
@@ -1,11 +1,9 @@
 #include "button.h"
-#include "string.h"
 
 //MultiButton
 
 #define HIGH              1
 #define LOW               0
-
 #define TICKS_INTERVAL    5	//ms
 
 const uint8_t  kDebounceTicks  = 3;
@@ -14,7 +12,6 @@ const uint16_t kLongTicks      = (1000/TICKS_INTERVAL);
 
 static struct Button* head_handle = NULL;
 
-
 /**
   * @brief  Initializes the button struct handle.
   * @param  handle: the button handle strcut.
diff --git a/button.h b/button.h
index d20629f..0427096 100644
--- a/button.h
+++ b/button.h
@@ -1,7 +1,8 @@
 #ifndef _BUTTON_H_
 #define _BUTTON_H_
 
-#include <stdint.h>
+#include "stdint.h"
+#include "string.h"
 
 typedef void (*CallBackFunc)(void);