Problem 68. Kaprekar Steps
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The behavior at x=6174 is artifically set to 0, which taints the purerecursive solution, but hey it was cool problem!
The K constant is 495 for 3 digits.
So the test with 691 is wrong.
Why tests with only one digit ?
Did I miss something ?
I don't understand the Test Suite for x = 3 and x = 1 too. what should I do in this case?
For x=3, the steps are 30000003=2997, 99722799=7173, etc.
Problem description is confusing as there are different Kaprekar constants depending on the number of digits. [0 9 495 6174 for 1, 2,3 4 digits respectively.
getting this error:
Internal Server Error  Read
The server encountered an internal error or misconfiguration and was unable to complete your request.
Reference #3.c2c1ab8.1412090777.18623697
any ideas?
The problem should specify that any number with less than four digits should be filled up to four digits with leading zeros. (e.g. 3 > 0003)
Very nice and interesting problem!
I like the recursion aspect of this problem.
There is a small correction needed in the problem statement. Not all natural numbers, but 4 digit numbers can be reduced to Kaprekar number by the mentioned method. Similarly 3 digit numbers can be reduced to 495
https://en.wikipedia.org/wiki/D._R._Kaprekar
How it works x = 1？？？？？
For those confused with test cases 2,3 and 5, like myself before, do conversion to 4digit integer. Here is an example:
x = 1:
10000001 = 999
99900999 = 8991
99811899 = 8082
88200288 = 8532
85322358 = 6174
Therefore, y_correct = 5
love it!!!
Very nice. Took some few minutes to crack this.
What I did is to convert x into string and then use sort function.
nice problem
ATTENTION
This problem statement is poorly given and leaves out a crucial element the input number must always have 4 digits, so if 1 is the input, the first iteration should be 10000001. the second iteration should be 99900999. for the problem as stated, the test suite gives solutions that are incorrect.
Quite interesting!
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