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Hi everyone, let's do this question.

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You are given a string.

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Write a function to check whether the string is a palindrome or not.

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Now when you're doing this in an interview, feel free to ask any clarifying questions you have now.

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Probably you could ask what if only a single character string is given?

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Should I treat it as a palindrome?

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Now again, remember what's a palindrome?

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It's a string that reads the same forward and backward.

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For example, if you have the string a, b, c, b a right now forward.

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This is how it reads.

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Now if you read it backward also, it's the same.

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So that's what we call a palindrome.

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Now even if you don't know that you can ask that also in the interview.

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So feel free to ask any clarifying questions so that you understand the question very well.

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Now for this question.

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Is a single character string treated as a palindrome?

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Let's say that the interviewer responds yes.

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All right.

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Now, another question that you could probably ask is what should happen if the string input is empty?

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Now let's say the interviewer replies, you can assume it's a non empty string.

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So that means that only a non empty string will be passed.

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All right.

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Now another question that you could ask is what should be the output of the function.

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Now in this case we can say that let the output be true or false.

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So another question that you could ask is should lowercase and uppercase alphabets be treated as different.

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Or should they be treated as the same like a and a?

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Now let's say that the interviewer responds and says treat them differently.

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All right.

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By this point you have got a good understanding of the question.

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Now let's proceed and write some test cases.

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Now remember test cases are just various inputs.

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And what output is expected if those inputs are given.

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Now in the interview you can take the help of the interviewer.

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You can ask him or her is it okay if we come up with a few test cases together?

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So that's a good practice.

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So you can always do that.

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Now let's go ahead and make some test cases.

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Let's say the input string is Malayalam.

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So this is my mother tongue.

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And you can see that it reads forward and backward the same.

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Right.

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So if this is the input the output should be true.

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Now what if the input is AA.

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In this case also it's the same right.

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So the output has to be true.

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Now what if the input is just a single character string.

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So the output has to be true.

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So we clarified this from the interviewer.

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And what if the input is aa.

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Now this is lowercase and this is uppercase.

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So these are to be treated differently.

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So this is to return the answer as false.

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So we've got a good understanding of the question.

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And we have written out test cases to ensure that the interviewer and we are on the same page.

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And we also understood any edge cases that we need to take care.

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Write test.

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Writing test cases helps you identify whether you have missed any particular edge cases or particular

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inputs for which you need to take care that the output is correct.

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Now let's go ahead and see how we can solve this question.