21岁，身在大学，而且理论上被合适的异性包围着。
At 21? I was in college and, in theory, surrounded by eligible women.
改进算法不仅降低了传统算法的复杂度，而且理论上也能提高了传统算法的性能。
The improved algorithm not only reduces the complexity of the conventional algorithm, but also improves its performance in theory.
其合理性在于：同时拥有两者可能达到极其高的利润，而且理论上可以制造出运行得更好的机器。
Makes sense: having ownership over both can be extremely lucrative and, theoretically, enable a better-working machine.
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