Plural side

The plural side of a node is the side, either the top or the bottom, to which more than one line is connected. For example, a downward OR node has one line connected to the top, which thus is called the singular side, and two or more lines connected to the bottom, the plural side. An upward AND node has two or more lines connected to the top, the plural side, and one connected to the bottom, the singular side.

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