If we need a 7, this is the ones column, the twos, fours, eights, so here are our columns and this was our decimal system a moment ago, and I wanna express the number 7 and the only digits 0 I now have access to are zero and one, whereas, in decimal, dec meaning 10.

如果你需要7，这是一位，二位，四位，八位，这是位数,刚才说的十进制的位数，我想表达7而且,只能采用数字1与，在十进制中，dec意思是十。

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