# 746. Min Cost Climbing Stairs

Easy
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`

### 解題

func minCostClimbingStairs(cost []int) int {
dp := int{0}
dp = cost
dp = cost
for i:=2; i<len(cost); i++ {
if dp[i-1]<dp[i-2] {
dp[i] = dp[i-1] + cost[i]
} else {
dp[i] = dp[i-2] + cost[i]
}
}
if dp[len(cost)-1] < dp[len(cost)-2] {
return dp[len(cost)-1]
}
return dp[len(cost)-2]
}