/*
      *   Learn a batch from experience replay
      */
      for (int i = 0; i < BATCHSIZE; ++i) {
        // Prioritized experience replay : select a "significant" experience based on highest TDError
        int memId = xorRandInt(memory.size());
        for (int j = 1; j < PRIOTOURNAMENTSIZE; ++j) {
          int r = xorRandInt(memory.size());
          if (memory[r].TDError > memory[memId].TDError) {
            memId = r;
          }
        }
        if (xorRandDouble() < 0.15) {
          // Bypass the prioritized experience replay
          memId = xorRandInt(memory.size());
        }

        const Experience &exp = memory[memId];