Re: searching for missing element in an array



rossum <rossum48@xxxxxxxxxxxx> wrote:
On Thu, 29 May 2008 03:10:32 -0700 (PDT), srk <kumarsr@xxxxxxxxx>
wrote:

Hi,
Suppose we have n numbers(from 1 to n) and there is an array of size
n-1. How can we find, which number is missing from the array if
numbers 1 to n are being placed in array randomly.

Thanks
SRK
Total all the numbers in the array.

The numbers from 1 to n add up to (n * (n + 1)) / 2.

The difference is the missing number.

Yes, now we all know you know the trick. Thanks for doing his homework,
I guess he really learned something today :)

--
:wq
^X^Cy^K^X^C^C^C^C
.



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