Road and Flyover Planning

RadhaKrishna

www.geocities.com/hellokrishna

2 Roads Junction (?)

0 Flyovers

3 Road Junction

2 FlyOvers

4 Road Junction

6 Flyovers

N Road JunctionPeople from one road need access to N-1 RoadsSo N * (N-1) FlyoversAll the ways can have ground level access to next RoadSo N*(N-1) – NOne Pair of Roads (non-next) can be on ground levelSo N*(N-1)-N-2(For 3 road junction, non-next does not exist. So free left is same as non-next pair roads.

Optimizing 4 Road Junction

Make it 2 three-road junctions2 + 2 < 6