Combinatorial geometry is concerned with counting objects that arise in geometric Settings.

本文研究组合几何中的一个典型计数问题-整边多边形的计数问题。

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We have two lone pairs, so if we thought about what the bonds were everywhere, 5° it would be 109 . 5, but it's bent because we're only looking at the bonds, we're not counting the Lewis structures in naming our geometry, but they do affect the angles.

我们有两个孤对，所以如果我们考虑它会成怎样的键时，应该成109。,但它是折线型，因为我们只考虑成键，在几何形状里不考虑Lewis结构，但它会影响角度。

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