<p>You are given an integer array <code>cost</code> where <code>cost[i]</code> is the cost of <code>i<sup>th</sup></code> step on a staircase. Once you pay the cost, you can either climb one or two steps.</p>
<p>You can either start from the step with index <code>0</code>, or the step with index <code>1</code>.</p>
<p>Return <em>the minimum cost to reach the top of the floor</em>.</p>