Hi, I am solving Finding CB Number problem of array but could not pass all the test cases

#1

My code is : https://ide.codingblocks.com/s/202549
Can you tell me where I am getting wrong answers.

#2

Hello @gourav,

  1. How would you check for the divisibility by 5 n the following code?
    for(ll i=5;i<=30 && i*i<=a;i=i+6)
    {
    if(a%(i-2)==0 || a%(i+2)==0)
    return false;
    }
    Solution:
    Rather create a separate array and store all the CB numbers given in the question which are also the prime numbers.
    and then check the divisibility of a with the elements of that array one by one.

  2. Where are you checking if a is one of those CB number given in the question?

The logic you have applied is not sufficient.

Approach:

  1. check for all sub-strings of the given string of digits, starting from 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.

  2. Print the count

Hope, this would help.
Give a like if you are satisfied.

#3

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