Optimize stop factor after every found factor

src/FactorizationController.cpp

@@ -185,6 +185,16 @@ void FactorizationController::factorize() {
         emit factorsChanged();
         emit curFactNumberChanged();
 
+        // As a further optimization, we can adjust the stop factor to the sqrt of
+        // the new number being factorized, rather than keeping it at the original number.
+        // (This might make the progress bar jump radically)
+        if (m_useSqrtOptimization) {
+            m_stopFactor = static_cast<long long>(std::sqrt(m_currentFactNumber));
+        } else {
+            m_stopFactor = m_currentFactNumber - 1;
+        }
+        emit progressChanged();
+
         // Don't increase current factor, keep dividing by it until no longer divisible
     } else {
         m_currentFactor++;