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The real moat is users' dependence on you.

"Silence is never empty; it's full of potential."

I cannot fix on the hour, or the spot, or the look, or the words, which laid the foundation. It is too long ago. I was in the middle before I knew that I had begun.

離散數學和連續數學之間的相互作用是一些最有趣的問題所在。