removed loop

window.cpp

@@ -42,14 +42,8 @@ Window::Window(QWidget *parent)
                 dy = 8;
             m_cell[x + y * 9].setParent(this);
             m_cell[x + y * 9].setGeometry(x * 100 + dx, y * 100 + dy, 100, 100);
-            /* code */
-        }
-    }
-    // init signals
-    for (int x = 0; x < 9; x++)
-    {
-        for (int y = 0; y < 9; y++)
-        {
+
+            //connecting signals & slots
             for (int d = 0; d < 9; d++) // rows and columns
             {
                 connect(&m_cell[x + y * 9], SIGNAL(update(int)), &m_cell[x + d * 9], SLOT(removeOption(int)));
@@ -77,7 +71,7 @@ void Window::solveButtonClicked()
 {
     std::list<History *> hist;
     bool backtracking = false;
-    srand(time(NULL));
+    srand(time(NULL)); //random seed
     while (1)
     {
         if (backtracking)
@@ -140,11 +134,14 @@ void Window::solveButtonClicked()
     // qInfo("%d---:)");
 }
 
-void Window::clearButtonClicked(){
-    for(auto& x: m_cell){
+void Window::clearButtonClicked()
+{
+    for (auto &x : m_cell)
+    {
         if (x.collapsed)
             x.un();
     }
+    repaint();
     return;
 }
 void Window::setValue(int s)