Merged two std::vector::erase calls in cbm::tof::Clusterizer. Makes the algorithm a bit faster.

algo/detectors/tof/Clusterizer.cxx

@@ -231,9 +231,10 @@ namespace cbm::algo::tof
         ROOT::Math::XYZVector pos(posX, posY, 0.);
         cluster.add(pos, time, totSum, totSum, i1->second, i2->second);
 
-        // remove selected digis from pool
-        storDigi.erase(i2);
-        storDigi.erase(i1);
+        // remove digis at positions i1 and i2 from pool in efficient way (replaces two vector::erase calls).
+        std::copy(i1 + 1, i2, i1);
+        std::copy(i2 + 1, storDigi.end(), i2 - 1);
+        storDigi.resize(storDigi.size() - 2);
 
         if (AddNextChan(input, chan, cluster, clustersOut)) {
           return true;  // signal hit was already added