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Hi, everyone.

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So in this video, we are going to discuss about this question, climbing stairs.

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So in this question, what we have given to us is we are standing at the ground floor and we want to

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reach to the top.

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So these are insteps steps, these are steps and I want to rise to the top, so it is given willing

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to take any steps to reach to the top.

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And the condition is we can either climb one step or two step.

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So either I will take a jump of one or I will take a jump of two from each step and we need to return.

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How many distinct ways are there to climb to the top?

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So this is the question and it's a pretty simple question we can easily solved with the help of recursion.

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So see.

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Let me draw this diagram so I want to reach this step, and this is and minus one step.

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This is and my is step and and my next steps.

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So either I can take a jump of two or one.

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So basically I can reach this step and from and minus one by taking a step of one.

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Or I can reach this and step by taking a step of two from and minus two.

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Right.

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So the number of ways, the number of ways to reach and step is basically either you can come from and

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minus one step or you can come from and minus two.

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So that will be our course relation.

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I'm explaining again, I want to reach here so either I can come from and minus one by taking a step

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of one or I can count from and minus two by taking a step of two.

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So a number of ways to reach and will be the number of ways to reach and minus one, plus the number

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of these number of distinct ways to reach and minus two.

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So that will be our recursive relation and what will be our best case.

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So best case is.

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This is ground this is step one and this is ground level.

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So how many number of ways to reach at this step?

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Only one, right?

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I can take a jump of only one.

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So we know what is half of one.

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Half of one is one.

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Right, so we know the reconciliation, we know the base case, let's start writing the code.

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So the cold is going to be pretty simple.

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We are going to use recursion for solving this problem, so we will return integer number of distinct

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ways to climb to the top.

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Let's say the name of the function is count steps.

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So first, let's talk about the base case, so base cases, if the value of an is one, then how many

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steps?

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I need to take one step.

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Right, so they are done when similarly, if the value of any zero you are standing at the ground level,

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then how many steps to take?

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None.

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Right.

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So there is one way we need to return.

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How many distinct ways?

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So there is one.

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We do not do anything.

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So there is one way, right.

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Now, our caste relation was our answer was.

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No steps to reach and minus one plus number of steps to reach and minus two.

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And now we just need to call this function.

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So they don't count steps and and and that said, this is going to be the complete college right now

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and then I will submit.

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So summit.

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So since this is recursive cold, we are going to encounter a time limit exceeded,

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right, because this is recursive cold and we can easily convert this recursive code into a deep code,

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which we are going to do in our next video.

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And if you click here, we can see how many test cases our code is passing.

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So out of 45, if we have passed 21 test cases, our code is failing for the remaining test cases because

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of time limit.

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So we NextRadio, what they are going to do is we are going to convert the second resolution into DEPI

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solution.

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Right.

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So we will do that in our next video.

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So this is a tremendous device.

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I will see you in the next one.

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Thank you.