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Hi everyone.

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Let's do this question.

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Let's define a peculiar type of array in which each element is either an integer or another peculiar

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array.

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All right.

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So over here this indicates that you have a peculiar type of array.

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And each element is either an integer or again another peculiar array.

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So notice that this indicates recursion right.

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So this is a hint that we are dealing with something that can be solved with recursion.

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Now let's proceed.

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Assume that a peculiar array is never empty.

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Write a function that will take a peculiar array as its input and find the sum of its elements.

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All right, so we have to just take in that array and find the sum.

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If an array is an element.

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In the peculiar array, you have to convert it to its equivalent value.

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All right.

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So if the element is an array then you have to convert it to its equivalent value so that you can sum

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it with the other elements.

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All right.

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So otherwise you won't be able to sum an integer and an array.

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Now equivalent value of an array is the sum of its elements raised to the number which represents how

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far nested it is.

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So you have to raise it right.

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Raise to a power.

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So it's an exponent.

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For example two three.

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And then you have this element over here which is an array 412.

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Now for this to find the sum you have to two plus three.

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And then you have to convert this to its equivalent value.

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And over here it said that's four plus one plus two to the power two.

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Right.

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So it is raised to the number which represents how far nested it is.

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So this is nested in to level two right.

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So that's why we have to the power two over here.

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Now in this case we have one two.

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So we are adding these two.

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And then over here we have seven.

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And then we have this element over here.

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And we have two.

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So seven plus the equivalent value of this element plus two to the power two because this is the second

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level right.

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And for the equivalent value of this one over here notice we have three plus four to the power three

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because this is the third level.

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Now you can also say that what this is doing over here is that if you have let's say an array with just

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three elements one, two, three, what we're doing is one plus two plus three to the power one because

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this is of level one right.

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So we have these elements.

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So I hope you have understood the question.

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Let's again summarize what we have understood.

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So we will be given a non-empty peculiar array.

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And then we have to find the sum of that peculiar array.

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And the sum is the sum of the elements.

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Now if the element of the array is an is an array itself, then you have to convert.

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For example, over here you have two which is an element which is a three.

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This is an integer.

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So yes two and three can be added.

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But then the next element over here is 412.

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So there should be a comma over here.

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So that's 412.

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And if that is the case then this has to be converted to its equivalent number.

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Only then it can be added to two plus three.

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Right.

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And for this we have to find its sum which is four plus one plus two.

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And it has to be raised to the power where the level is, where it's raised, to the number which represents

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how far nested it is.

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So this is the this is two levels deep right.

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This is level one and this is level two.

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So that's why we are raising to the power two.

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Now in this example this was three levels deep.

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This is level one.

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This is level two.

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And then this is level three.

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So over here we have three plus four to the power three.

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And then we add that to seven and two and raise it to the power two.

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So we get the equivalent value of this element over here.

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And that is added to one and two.

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All right.

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So this is the question over here.

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And again notice over here we saw something interesting in the question.

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When we read it we it's mentioned over here we have a particular type of array.

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And each element is either an integer or another peculiar array.

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So this indicates recursion right.

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So we have something and something inside that can also be that something.

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So over here this indicates recursion.

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So these type of problems typically can be solved with recursion.

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All right.

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So we have read the question.

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We have understood it.

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Now let's proceed and write a few test cases so that we get a good understanding of the question.

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And then we will look at how we can solve this question.

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Again we have a few test cases over here.

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Let's again write a few more so that we get familiarized with the question.

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All right.

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Now let's take a very simple case.

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Let's say the array which is given to us is one, two, three.

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So in this case we just need to add these.

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All right.

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One plus two plus three which is equal to six.

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Right.

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And again over here the level is one.

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So we can say that we are raising this to the power one which does not change.

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Six.

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Right.

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The answer is still six.

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Now let's say we have this array over here one two.

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And then this element is not an integer.

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It's an it's another array.

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Right.

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So in this case we have to convert this to its equivalent value so that we can add it to these two.

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So the answer over here will be one plus two plus three to the power two.

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Because this is level one.

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This bracket is level one and this bracket is level two.

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Right.

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So we have to do three to the power two.

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And this is nine nine plus two is 11 plus one is 12.

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So this gives us the answer is 12.

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And again in the question it's mentioned that the input will be non-empty.

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So we don't need to consider that case right now.

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Let's say the input is this one over here it's a little bit more complicated.

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So we have one we have two.

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So basically we need to convert this array into its equivalent value which is three plus four to the

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power of this level of the brackets.

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Right.

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So this is level one.

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This one over here is level one.

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Level one.

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This is level two right.

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This also is level two right.

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And this is within level two.

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So this is level three.

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So over here this can be converted to three plus four which is seven to the power two.

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So that is seven square right.

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Now what about this value over here.

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This two is in level three right.

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So we have to do two cube.

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So we get eight.

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Now we have still level two over here right.

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These brackets.

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So we have to do eight to the power two which gives us 64.

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So we have everything now in level one.

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So we just need to add these up.

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127 square is 49 and eight square is 64.

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So let's add them one plus two plus 49 plus 64.

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And again we could raise this to power one which is the same thing right.

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But it does not change the answer.

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And this is equal to 116.

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And this is what is expected from the function that we have to write.

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So we have got a good understanding of the question.

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Now let's proceed and think through the logic or the method which we can use to solve this problem.