Stick graphs are defined as follows. Let A (respectively B) be a set of vertical (respectively horizontal) segments in the plane such that the bottom endpoints of the segments in A and the left endpoints of the segments in B lie on the same ground straight line with slope -1. The Stick graph defined by A and B, which is necessarily bipartite, is the intersection graph of the segments in A with the segments in B. We answer an open problem by showing that recognizing Stick graphs is NP-complete.

翻译：Stick 图形定义如下。 让 A (分别是B) 成为平面上一组垂直(分别是水平水平)段,这样A段的底端点和B段的左端点就位于与斜度相同的地面直线 - 1。 A 和 B 定义的 stick 图形必然是双边的, 是 A 段与 B 段的交叉图。 我们通过显示确认 stick 图形是 NP 完整, 来回答一个尚未解决的问题 。