## Editorial for Mock CCC '24 Contest 1 J3 - RGB Words

Remember to use this editorial

**only**when stuck, and**not to copy-paste code from it**. Please be respectful to the problem author and editorialist.**Submitting an official solution before solving the problem yourself is a bannable offence.**Author:

To solve this problem, we aim to count the number of "RGB-words" present in a given string.

## Subtask 1 and 2

This subtask can be solved using simple brute force. We can store the indices or the`R`

's and `B`

's, and store the number of `G`

's in a frequency array. We can loop through all the `R`

indices and loop through the `B`

indices. If the `B`

index is greater than the `R`

index and freq[`B`

index] freq[`R`

index] , we can add to the total, If the frequency difference ever becomes , we can break and skip to the next `R`

index.
**Time Complexity:**

## Subtask 3

The final optimization is to use frequency arrays for`R`

's and `B`

's and to store the indices of the `G`

's. We can realize that the number of RGB-words containing the G[] is the number of `R`

's from Rfreq[G[]] to Rfreq[G[]] if they exist, multiplied by the number of `B`

's from Bfreq[G[]] to Bfreq[G[]] if they exist.
**Time Complexity:**

## Comments

good job