Ada and the Staircase

There is a big staircase with $N$ steps (numbered $1$ through $N$) in ChefLand. Let's denote the height of the top of step $i$ by $h_i$. Chef Ada is currently under the staircase at height $0$ and she wants to reach the top of the staircase (the top of the last step). However, she can only jump from height $h_i$ to the top of a step at height $h_f$ if $h_f-h_i \le K$. To help Ada, we are going to