How should I practice Count Good Strings?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Commvault online assessment problems in FastPrep.

Is Count Good Strings associated with Commvault?

FastPrep tags this as a Commvault coding interview or online assessment practice problem when the problem catalog has that company context.

Problem · Dynamic Programming

Count Good Strings

Learn this problem

● MediumCommvaultOA

Problem statement

There is a string of length 2N containing only character A and B. The string is called good string if the following two conditions are satisfied:

The number of A and number of B in that string will be same and that is N, means N numbers of A and N numbers of B will be present in that string.

The number of A will be always greater than or equal to the number of B in any prefix string of that string.

Now you are given N and you need to count the number of good strings of length 2N, the answer may be very large so return the answer in modulo 10000.

Function

countGoodStrings(N: int) → int

Examples

Example 1

N = 3return = 5

Here are the good strings of length 2N when N=3:

"AAABBB" good
"AABABB" good
"AABBAB" good
"ABAABB" good
"ABABAB" good

"BABABA" is not a good string because the number of Bs is greater than the number of As in the prefix "BA". Therefore, the count of good strings is 5.

Constraints

o_o

Problem statement

Function

Examples

Example 1

Constraints

More Commvault problems