I am getting WA in TestCase 1, 2 ,3

#1

some hint?
i know in this question , need to count prime number.

#2

@Vipin_coder,
No you don’t need to check for prime numbers buddy. You have to check for divisibility with the given numbers, that’s it.

Suggested Approach:

  1. check for all sub-strings of the given string of digits, starting from the all strings of length 1 and then gradually checking for the strings of increasing size:

1.1. check if the sub-string is CB number: for this, create a function
1.1.1. if sub-string is 1 or 0 return false.
1.1.2. if sub-string is any of the {2,3,5,7,11,13,17,19,23,29}, then return true.
1.1.3. if sub-string is divisible by any of the {2,3,5,7,11,13,17,19,23,29}, then return false.
1.1.4. return false

1.2. now if it is a substring:
1.2.1. call a function that marks the index as visited for indexes which are part of that CB number.

1.3. increment the count for CB number.

  1. Print the count
#3

mean i need to count first fro 1 length of substrings, then for all 2 length of substring and so on.??

#4

@Vipin_coder,
Yes but mark in case you are taking the substring and that is a CB number then make sure you mark the visited for the indexes.

Sample input:
6
441441
Correct Answer: 2
Here 41,41 are the CB numbers, hence the answer will be 2.

#5

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