Chef and Deforestation

The Chef has come to a forest. He sees N trees in a line. He wants to tie a rope from the top of one tree to the top of another. To successfully tie this rope, he needs to cut the trees that get in the way of the rope. However, he does not like this kind of deforestation and wants your help to choose the best pair of trees between which to tie the rope. Formally, you are given N trees on the X-ax