I'm trying for below program?Its showing output is 8,How?

Question

int array[]={0,2,4,6,8,10};

what is the value of array[array[2]];? Its showing ans is 8

We tried for this question,but not getting why answer is 8

Possible duplicate of [Why does the indexing start with zero in 'C'?](https://stackoverflow.com/questions/7320686/why-does-the-indexing-start-with-zero-in-c) — Athul Nath, Mar 29 '18 at 04:58
In order to improve your question (and maybe loose some of the downvotes) you should explain how the output of 8 conflicts with the logic you and your team have sketched, i.e. you try to explain what *should* be the output in your opinion. That will improve the answer by making it more clear what exactly you are asking about. For example, the answerers below seem all to have guessed that you expected an output of 10. If that is the case, [edit] your question to state that explicitily and add the logical steps behind that. — Yunnosch, Mar 29 '18 at 05:54
What was your effort so far. What output do you expect and why? — Gerhardh, Mar 29 '18 at 07:27

I. Ahmed · Answer 1 · 2018-03-29T05:00:36.107

1

To understand the it, need some array and indexing foundation.

For example:

int array[]={0,2,4,6,8,10};

means

a[0] = 0, a1 = 2, a[2] = 4 and so on.

The C/C++ array index start from 0, and indexes are valid upto 0..length-1

So, array[2] --> 4, the third element of the array.

Then, array[array[2]]-->array[4]-->8, which is the fifth element of the array.

Please check the following source for more information: C++ Array reference

edited Mar 29 '18 at 05:00

answered Mar 29 '18 at 04:44

I. Ahmed

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I changed "forth" to "fifth" because it looked like a simple mistake. Change it back if I'm wrong. – user253751 Mar 29 '18 at 04:51
Thanks for the best Explanation – varsha chavan Mar 29 '18 at 05:40

score 0 · Answer 2 · edited Mar 29 '18 at 05:04

0

int array[]={0,2,4,6,8,10};

You have declared an int array of six integer values.It will be stored as :

array[0] = 0
array[1] = 2
array[2] = 4
array[3] = 6
array[4] = 8
array[5] = 10

array[array[2]] in this line you are trying to retrieve the value of the array of index array[2](which gives you 4 as array[2] = 4 ). It will be like array[4] which gives you 8.

edited Mar 29 '18 at 05:04

Robel Sharma

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answered Mar 29 '18 at 04:54

Ravi

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score 0 · Answer 3 · answered Mar 29 '18 at 05:25

a simple answer will be to understand how this line is evaluated first when you declare:

int array[]={0,2,4,6,8,10};

you get:

array[0] = 0
array[1] = 2
array[2] = 4
array[3] = 6
array[4] = 8
array[5] = 10

now when you try and evaluate array[array[2]] :

the statment array[2] is evaluated first to 4 then the array[4] is evaluate and it evaluates to 8

array[array[2]] --> array[ ( array[2] = 4 ) ] --> array[ 4 ] --> 8

hope this clears it up a bit

Thanks for such explanation.Its easy to understand. – varsha chavan Mar 29 '18 at 05:41 — varsha chavan, Mar 29 '18 at 05:41

score 0 · Answer 4 · answered Mar 29 '18 at 05:34

0

According to this array:

array[0] = 0
array[1] = 2
array[2] = 4
array[3] = 6
array[4] = 8
array[5] = 10

you want to get value for : array[array[2]]

so 1st get what is inside: array[2]

array[2] : 4

so array[array[2]] --> array[4]

therefor value is : 8

answered Mar 29 '18 at 05:34

MinA

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Helpful Contents...Thanks – varsha chavan Mar 29 '18 at 05:41

score 0 · Answer 5 · edited Mar 29 '18 at 13:43

Ok , since it is here considered a multi-dimensional array (which means an array within an array) therefore, you need to find the element corresponding to the index of the inner array then afterwards the value would be actually the index of the outer array.

For example:

int array1[]: {1,2,3,4,5,6,7,8,9,10} int array[array1[3]]

The output of the following would be : First get the value of the inner array which would be: 4 Afterwards, this would be the index number of the outer array which will correspond to value within the array which will be: 5 .

I'm trying for below program?Its showing output is 8,How?

5 Answers5