Goldman Sachs Software Developer interview questions

there are two cities opposite each other across a river. You can build a bridge between two buildings, one from each city, with the same value so that it does not intersect another bridge. You need to find the maximum number of bridges that can be constructed. Ex:- 1 2 3 4 and another side 3 4 2 1. So you can connect 3–3 and 4–4 without intersecting. So the answer is 2.