diff --git a/NEWS.md b/NEWS.md
index 408a8a95..07bf110e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -6,6 +6,7 @@ Red Panda C++ Version 0.14.0
   - fix: code folding calcuation not correct when some codes are folded and editing after them
   - enhancement: code completion ui redesigned
   - fix: mainwindow action's short cut doesn't work,  if the action is not in menu or toolbar
+  - fix: when run all cases for a problem, processing of output is slow
 
 Red Panda C++ Version 0.13.4
   - fix: when copy comments, don't auto indent
diff --git a/RedPandaIDE/compiler/compilermanager.cpp b/RedPandaIDE/compiler/compilermanager.cpp
index 14035398..fe32c699 100644
--- a/RedPandaIDE/compiler/compilermanager.cpp
+++ b/RedPandaIDE/compiler/compilermanager.cpp
@@ -325,7 +325,7 @@ void CompilerManager::runProblem(const QString &filename, const QString &argumen
     connect(mRunner, &Runner::runErrorOccurred, pMainWindow ,&MainWindow::onRunErrorOccured);
     connect(execRunner, &OJProblemCasesRunner::caseStarted, pMainWindow, &MainWindow::onOJProblemCaseStarted);
     connect(execRunner, &OJProblemCasesRunner::caseFinished, pMainWindow, &MainWindow::onOJProblemCaseFinished);
-    connect(execRunner, &OJProblemCasesRunner::newOutputLineGetted, pMainWindow, &MainWindow::onOJProblemCaseNewOutputLineGetted);
+    connect(execRunner, &OJProblemCasesRunner::newOutputGetted, pMainWindow, &MainWindow::onOJProblemCaseNewOutputGetted);
     mRunner->start();
 }
 
diff --git a/RedPandaIDE/compiler/ojproblemcasesrunner.cpp b/RedPandaIDE/compiler/ojproblemcasesrunner.cpp
index 32129fd4..e2ccf6e2 100644
--- a/RedPandaIDE/compiler/ojproblemcasesrunner.cpp
+++ b/RedPandaIDE/compiler/ojproblemcasesrunner.cpp
@@ -79,10 +79,10 @@ void OJProblemCasesRunner::runCase(int index,POJProblemCase problemCase)
     }
     QByteArray readed;
     QByteArray buffer;
-    QStringList outputLines;
+    QByteArray output;
     while (true) {
         process.waitForFinished(100);
-        readed = process.readAll();
+        readed = process.read(5001);
         buffer += readed;
         if (process.state()!=QProcess::Running) {
             break;
@@ -97,30 +97,15 @@ void OJProblemCasesRunner::runCase(int index,POJProblemCase problemCase)
         }
         if (errorOccurred)
             break;
-        QList<QByteArray> lines = splitByteArrayToLines(buffer);
-//        qDebug()<<"----do buffer----";
-//        qDebug()<<readed;
-//        qDebug()<<buffer;
-//        qDebug()<<lines.count();
-        if (lines.count()>=2) {
-            for (int i=0;i<lines.count()-1;i++) {
-                QString line = QString::fromLocal8Bit(lines[i]);
-                emit newOutputLineGetted(problemCase->getId(),line);
-                outputLines.append(line);
-            }
-            buffer = lines.last();
-            while (buffer.endsWith('\0')) {
-                buffer.remove(buffer.length()-1,1);
-            }
+        if (buffer.length()>5000) {
+            emit newOutputGetted(problemCase->getId(),QString::fromLocal8Bit(buffer));
+            output.append(buffer);
+            buffer.clear();
         }
     }
-    buffer += process.readAll();
-    QList<QByteArray> lines = splitByteArrayToLines(buffer);
-    for (int i=0;i<lines.count();i++) {
-        QString line = QString::fromLocal8Bit(lines[i]);
-        emit newOutputLineGetted(problemCase->getId(),line);
-        outputLines.append(line);
-    }
+    if (process.state() == QProcess::ProcessState::NotRunning)
+        buffer += process.readAll();
+    output.append(buffer);
     if (errorOccurred) {
         //qDebug()<<"process error:"<<process.error();
         switch (process.error()) {
@@ -144,7 +129,7 @@ void OJProblemCasesRunner::runCase(int index,POJProblemCase problemCase)
             break;
         }
     }
-    problemCase->output = linesToText(outputLines);
+    problemCase->output = QString::fromLocal8Bit(output);
 }
 
 void OJProblemCasesRunner::run()
diff --git a/RedPandaIDE/compiler/ojproblemcasesrunner.h b/RedPandaIDE/compiler/ojproblemcasesrunner.h
index 1e28b9b9..c4d127b3 100644
--- a/RedPandaIDE/compiler/ojproblemcasesrunner.h
+++ b/RedPandaIDE/compiler/ojproblemcasesrunner.h
@@ -32,7 +32,7 @@ public:
 signals:
     void caseStarted(const QString& id, int current, int total);
     void caseFinished(const QString& id, int current, int total);
-    void newOutputLineGetted(const QString&id, const QString& newOutputLine);
+    void newOutputGetted(const QString&id, const QString& newOutputLine);
 private:
     void runCase(int index, POJProblemCase problemCase);
 private:
diff --git a/RedPandaIDE/mainwindow.cpp b/RedPandaIDE/mainwindow.cpp
index af511bd0..5d4d887f 100644
--- a/RedPandaIDE/mainwindow.cpp
+++ b/RedPandaIDE/mainwindow.cpp
@@ -3117,9 +3117,9 @@ void MainWindow::onProblemCaseIndexChanged(const QModelIndex &current, const QMo
         POJProblemCase problemCase = mOJProblemModel.getCase(idx.row());
         if (problemCase) {
             ui->btnRemoveProblemCase->setEnabled(true);
-            ui->txtProblemCaseInput->setText(problemCase->input);
+            ui->txtProblemCaseInput->setPlainText(problemCase->input);
             ui->txtProblemCaseInput->setReadOnly(false);
-            ui->txtProblemCaseExpected->setText(problemCase->expected);
+            ui->txtProblemCaseExpected->setPlainText(problemCase->expected);
             ui->txtProblemCaseExpected->setReadOnly(false);
             updateProblemCaseOutput(problemCase);
             return;
@@ -4081,9 +4081,9 @@ void MainWindow::onOJProblemCaseFinished(const QString& id, int current, int tot
     updateProblemTitle();
 }
 
-void MainWindow::onOJProblemCaseNewOutputLineGetted(const QString &, const QString &line)
+void MainWindow::onOJProblemCaseNewOutputGetted(const QString &, const QString &line)
 {
-    ui->txtProblemCaseOutput->append(line);
+    ui->txtProblemCaseOutput->appendPlainText(line);
 }
 
 void MainWindow::cleanUpCPUDialog()
@@ -5519,7 +5519,7 @@ void MainWindow::doCompileRun(RunType runType)
 void MainWindow::updateProblemCaseOutput(POJProblemCase problemCase)
 {
     ui->txtProblemCaseOutput->clear();
-    ui->txtProblemCaseOutput->setText(problemCase->output);
+    ui->txtProblemCaseOutput->setPlainText(problemCase->output);
     if (problemCase->testState == ProblemCaseTestState::Failed) {
         QStringList output = textToLines(problemCase->output);
         QStringList expected = textToLines(problemCase->expected);
@@ -5666,7 +5666,6 @@ void MainWindow::on_actionExport_As_HTML_triggered()
 
 void MainWindow::on_actionMove_To_Other_View_triggered()
 {
-    qDebug()<<"test";
     Editor * editor = mEditorList->getEditor();
     if (editor) {
         mEditorList->swapEditor(editor);
diff --git a/RedPandaIDE/mainwindow.h b/RedPandaIDE/mainwindow.h
index a0bf2324..c938f3ba 100644
--- a/RedPandaIDE/mainwindow.h
+++ b/RedPandaIDE/mainwindow.h
@@ -194,7 +194,7 @@ public slots:
     void onRunProblemFinished();
     void onOJProblemCaseStarted(const QString& id, int current, int total);
     void onOJProblemCaseFinished(const QString& id, int current, int total);
-    void onOJProblemCaseNewOutputLineGetted(const QString& id, const QString& line);
+    void onOJProblemCaseNewOutputGetted(const QString& id, const QString& line);
     void cleanUpCPUDialog();
     void onDebugCommandInput(const QString& command);
     void onDebugEvaluateInput();
diff --git a/RedPandaIDE/mainwindow.ui b/RedPandaIDE/mainwindow.ui
index af778c50..480c1d88 100644
--- a/RedPandaIDE/mainwindow.ui
+++ b/RedPandaIDE/mainwindow.ui
@@ -506,7 +506,7 @@
         <enum>QTabWidget::South</enum>
        </property>
        <property name="currentIndex">
-        <number>5</number>
+        <number>6</number>
        </property>
        <property name="iconSize">
         <size>
@@ -1348,33 +1348,24 @@
                </property>
               </widget>
              </item>
-             <item row="1" column="0">
-              <widget class="QTextEdit" name="txtProblemCaseInput">
+             <item row="1" column="1">
+              <widget class="QPlainTextEdit" name="txtProblemCaseOutput">
                <property name="lineWrapMode">
-                <enum>QTextEdit::NoWrap</enum>
-               </property>
-               <property name="acceptRichText">
-                <bool>false</bool>
+                <enum>QPlainTextEdit::NoWrap</enum>
                </property>
               </widget>
              </item>
-             <item row="1" column="1">
-              <widget class="QTextEdit" name="txtProblemCaseOutput">
+             <item row="1" column="0">
+              <widget class="QPlainTextEdit" name="txtProblemCaseInput">
                <property name="lineWrapMode">
-                <enum>QTextEdit::NoWrap</enum>
-               </property>
-               <property name="readOnly">
-                <bool>true</bool>
+                <enum>QPlainTextEdit::NoWrap</enum>
                </property>
               </widget>
              </item>
              <item row="1" column="2">
-              <widget class="QTextEdit" name="txtProblemCaseExpected">
+              <widget class="QPlainTextEdit" name="txtProblemCaseExpected">
                <property name="lineWrapMode">
-                <enum>QTextEdit::NoWrap</enum>
-               </property>
-               <property name="acceptRichText">
-                <bool>false</bool>
+                <enum>QPlainTextEdit::NoWrap</enum>
                </property>
               </widget>
              </item>