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Hey there and welcome back.

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So over here we have another interesting question which is called minimum cost climbing stairs.

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So the question reads you are given an integer array cost where cost at index I is the cost of the ith

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step on a staircase.

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Once you pay the cost, you can either climb 1 or 2 steps.

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You can either start from the step with index zero or the step with index one.

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Return the minimum cost to reach the top of the floor, and it's given that the length of the cost array

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will be definitely greater than or equal to two.

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So this is an interesting question.

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And we are also given an example.

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So let's say the cost array which is given to us has three elements one, two and three.

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So the indices over here are zero one and two.

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So these are the three steps.

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This is the step with index zero.

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This is the step at index one.

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And this is the step at index two.

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And then this is the destination.

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Notice that the destination is beyond the last index in the cost array.

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And the expected output in this case is equal to two because we can start at this step over here.

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Because in the question it's mentioned that we can either start from the step with index zero or the

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step with index one.

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So let's say we are starting over here.

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That is at the step with index one.

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And then we'll pay this amount which is two.

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And we can use this step.

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And we can either go one step or two steps.

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But it's good to use two steps because that will ensure that we have reached the destination.

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So that's why the total cost involved in this case would be two, because we're just using this step

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over here.

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So we will have to pay two and we will be able to reach the destination.

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Now, what are a few other ways in which we could have reached the top or the destination?

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We could have started at this step over here with index zero, and we could first take two steps and

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then take one step.

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So what would be the total cost involved in this case?

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Because we are using this step.

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And this step will have to pay the cost at these two indices which is one and three.

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So the total cost would be one plus three which is equal to four.

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Okay.

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Now another way in which we could have reached the top could be by first taking one step from this step

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and then taking two steps.

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Okay.

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So in this case we're using this step over here.

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And we're using this step over here.

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So we would have to pay one plus two which is a total of three.

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So in this way, you can see there are multiple ways to reach the top.

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And the question asks us to identify the path which would require the minimum amount to be paid.

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And then we'll have to output that particular amount.

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So this is the question at hand.

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Now in the next video let's go ahead and see how we can solve this.