unary Boolean operator

例句：

1. 1.The unary approach to problem-solving is not always effective.
   单一解决问题的方法并不总是有效的。
2. 2.The unary theorem states that the sum of two numbers is equal to their product.
   一元定理表明两个数的和等于它们的积。
3. 3. In a binary system, each number has only two possible values.
   在二进制系统中，每个数字只有两种可能的值。