Min Cost Climbing Stairs

You are given an integer array `cost` where `cost[i]` is the cost of `ith` step on a staircase. Once you pay the cost, you can either climb one or two steps. You can either start from the step with index `0`, or the step with index `1`. Return _the minimum cost to reach the top of the floor_.   **Example 1:** **Input:** cost = [10,15,20] **Output:** 15 **Explanation:** You will start at index 1. - Pay 15 and climb two steps to reach the top. The total cost is 15. ``` **Example 2:** **Input:** cost = [1,100,1,1,1,100,1,1,100,1] **Output:** 6 **Explanation:** You will start at index 0. - Pay 1 and climb two steps to reach index 2. - Pay 1 and climb two steps to reach index 4. - Pay 1 and climb two steps to reach index 6. - Pay 1 and climb one step to reach index 7. - Pay 1 and climb two steps to reach index 9. - Pay 1 and climb one step to reach the top. The total cost is 6. ```   **Constraints:** - `2 <= cost.length <= 1000` - `0 <= cost[i] <= 999`