diff --git a/app/src/main/java/com/qwe7002/telegram_rc/chat_command_service.java b/app/src/main/java/com/qwe7002/telegram_rc/chat_command_service.java
index df9c3dc7..c3bc81dc 100644
--- a/app/src/main/java/com/qwe7002/telegram_rc/chat_command_service.java
+++ b/app/src/main/java/com/qwe7002/telegram_rc/chat_command_service.java
@@ -289,7 +289,7 @@ private void receive_handle(JsonObject result_obj) {
                                         break;
                                     }
                                     Thread.sleep(100);
-                                    count++;
+                                    ++count;
                                 }
                                 Thread.sleep(1000);
                             } catch (InterruptedException e) {
@@ -337,7 +337,7 @@ private void receive_handle(JsonObject result_obj) {
                     String msg_send_to = public_func.get_send_phone_number(msg_send_list[1]);
                     if (public_func.is_phone_number(msg_send_to)) {
                         StringBuilder msg_send_content = new StringBuilder();
-                        for (int i = 2; i < msg_send_list.length; i++) {
+                        for (int i = 2; i < msg_send_list.length; ++i) {
                             if (msg_send_list.length != 3 && i != 2) {
                                 msg_send_content.append("\n");
                             }
@@ -618,7 +618,7 @@ public void run() {
                     public_func.write_log(context, "Connection to the Telegram API service failed,try again after " + sleep_time + " seconds.");
                     magnification = 1;
                     if (error_magnification <= 59) {
-                        error_magnification++;
+                        ++error_magnification;
                     }
                     try {
                         Thread.sleep(sleep_time * 1000);
@@ -645,7 +645,7 @@ public void run() {
                         }
                     }
                     if (magnification <= 11) {
-                        magnification++;
+                        ++magnification;
                     }
                 } else {
                     public_func.write_log(context, "response code:" + response.code());
diff --git a/app/src/main/java/com/qwe7002/telegram_rc/public_func.java b/app/src/main/java/com/qwe7002/telegram_rc/public_func.java
index 918f64e6..98c474a0 100644
--- a/app/src/main/java/com/qwe7002/telegram_rc/public_func.java
+++ b/app/src/main/java/com/qwe7002/telegram_rc/public_func.java
@@ -91,7 +91,7 @@ static int parse_int(String int_str) {
 
     static String get_send_phone_number(String phone_number) {
         StringBuilder result = new StringBuilder();
-        for (int i = 0; i < phone_number.length(); i++) {
+        for (int i = 0; i < phone_number.length(); ++i) {
             char c = phone_number.charAt(i);
             if (c == '+' || Character.isDigit(c)) {
                 result.append(c);
@@ -476,7 +476,7 @@ static String read_file_last_line(Context context, @SuppressWarnings("SameParame
                     if (count == (line - 1)) {
                         break;
                     }
-                    count++;
+                    ++count;
                 }
             }
             return builder.toString();
diff --git a/app/src/main/java/com/qwe7002/telegram_rc/sms_receiver.java b/app/src/main/java/com/qwe7002/telegram_rc/sms_receiver.java
index 9aecd6b9..7478429e 100644
--- a/app/src/main/java/com/qwe7002/telegram_rc/sms_receiver.java
+++ b/app/src/main/java/com/qwe7002/telegram_rc/sms_receiver.java
@@ -60,7 +60,7 @@ public void onReceive(final Context context, Intent intent) {
         Object[] pdus = (Object[]) extras.get("pdus");
         assert pdus != null;
         final SmsMessage[] messages = new SmsMessage[pdus.length];
-        for (int i = 0; i < pdus.length; i++) {
+        for (int i = 0; i < pdus.length; ++i) {
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                 String format = extras.getString("format");
                 messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i], format);
@@ -143,7 +143,7 @@ public void onReceive(final Context context, Intent intent) {
                         } catch (InterruptedException e) {
                             e.printStackTrace();
                         }
-                        loop_count++;
+                        ++loop_count;
                     }
                     String status = context.getString(R.string.action_failed);
                     WifiManager wifiManager = (WifiManager) context.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
@@ -169,7 +169,7 @@ public void onReceive(final Context context, Intent intent) {
                                     break;
                                 }
                                 Thread.sleep(100);
-                                count++;
+                                ++count;
                             }
                             Thread.sleep(1000);//Wait 3   second to avoid startup failure
                         } catch (InterruptedException e) {
@@ -196,7 +196,7 @@ public void onReceive(final Context context, Intent intent) {
                             } catch (InterruptedException e) {
                                 e.printStackTrace();
                             }
-                            loop_count++;
+                            ++loop_count;
                         }
                     }
                     raw_request_body_text = context.getString(R.string.system_message_head) + "\n" + context.getString(R.string.switch_data);
@@ -215,7 +215,7 @@ public void onReceive(final Context context, Intent intent) {
                     String msg_send_to = public_func.get_send_phone_number(msg_send_list[0]);
                     if (public_func.is_phone_number(msg_send_to) && msg_send_list.length != 1) {
                         StringBuilder msg_send_content = new StringBuilder();
-                        for (int i = 1; i < msg_send_list.length; i++) {
+                        for (int i = 1; i < msg_send_list.length; ++i) {
                             if (msg_send_list.length != 2 && i != 1) {
                                 msg_send_content.append("\n");
                             }