Your comparison function does not account for integer over/under flow ;-) that's the point of these fixed tests

I think you don't need if(dec[i] > 0)

They're not, the description was awkwardly worded. If the input cannot be arranged into a square, it is invalid and you have to return "No"

You should provide an example...

Here's one:

Testing for [1, 0, 1]
It should work for random inputs too: 'Yes' should equal 'No'

Same for [1, 1]

Some python tests are bad, C tests too.

IMHO. Real challenge for those who want better understand how work lists on lower level (C lang).

If it's a problem with your algo, please mark as a question, not an issue. EmperorMigx is correct, you have to allocate memory and mind your type.

Description nothing says about 'sabbatical' in capital letters and if input string has only one 'a' it should be counted once instead of triple 'a' from 'sabbatical'.

I assumed input string s as 'sabbatical'. Thx.

The numbers of letters from 'sabbatical' that are present in string s.

You're not doing that. Read the description again.

Hi, there's no issue here. You're adding up all 5 letters in the input 'cCdvi' where cCdvi > 5 + 10 + 9 = 24, meanwhile 'd' and 'v' are not in the word 'sabbatical', so they should not be counted.