removed redundant connections between cells, added repaint and sleep to...

removed redundant connections between cells, added repaint and sleep to backtracking for visualisation

window.cpp

@@ -58,6 +58,8 @@ Window::Window(QWidget *parent)
             {
                 for (int y1 = b; y1 < b + 3; y1++)
                 {
+                    if(x1 == x || y1 == y)
+                        continue;
                     connect(&m_cell[x + y * 9], SIGNAL(update(int)), &m_cell[x1 + y1 * 9], SLOT(removeOption(int)));
 
                     connect(&m_cell[x + y * 9], SIGNAL(undo(int)), &m_cell[x1 + y1 * 9], SLOT(addOption(int)));
@@ -74,6 +76,8 @@ void Window::solveButtonClicked()
     srand(time(NULL)); //random seed
     while (1)
     {
+        repaint(); // draw cells again
+        QThread::msleep(m_delay);
         if (backtracking)
         {
             hist.back()->cell->un();
@@ -84,6 +88,8 @@ void Window::solveButtonClicked()
             }
             backtracking = false;
             int choiceNr = rand() % hist.back()->index.size();         // choose a random number;
+            repaint(); // draw cells again
+            QThread::msleep(m_delay);
             hist.back()->cell->collapse(hist.back()->index[choiceNr]); // collapse cell with chosen number;
             std::vector<int>::iterator it;
             it = hist.back()->index.begin() + choiceNr;
@@ -128,8 +134,6 @@ void Window::solveButtonClicked()
             hist.push_back(new History(b[choiceCell], b[choiceCell]->index, choiceNr));
             b[choiceCell]->collapse(b[choiceCell]->index[choiceNr]); // collapse that random cell with chosen number;
         }
-        repaint(); // draw cells again
-        QThread::msleep(m_delay);
     }
     // qInfo("%d---:)");
 }
@@ -141,7 +145,6 @@ void Window::clearButtonClicked()
         if (x.collapsed)
             x.un();
     }
-    repaint();
     return;
 }
 void Window::setValue(int s)