Maximum length subsequence possible of the form R^N K^N

Given a string containing only two characters i.e. R and K (like RRKRRKKKKK). The task is to find the maximum value of N for a subsequence possible of the form R---N times and then K---N times (i.e. of the form R^N K^N).

Note: String of k should be started after the string of R i.e. first k that would be considered for 'K' string must occur after the last R of the 'R' string in the given string. Also, the length of the resulting subsequence will be 2*N.

Examples: 

Input: RRRKRRKKRRKKK 
Output: 5 
If we take R's at indexes 0, 1, 2, 4, 5 and K's at indexes 6, 7, 10, 11, 12 
then we get a maximum subsequence of the form R^N K^N, where N = 5.

Input: KKKKRRRRK 
Output: 1 
If we take R at index 4( or 5 or 6 or 7) and K at index 8 
then we get the desired subsequence with N = 1. 

Approach: 

1. Calculate the number of R's before a K .
2. Calculate the number of K's after a K, including that K.
3. Store them in a table with a number of R's in table[x][0] and a number of K's in table[x][1].
4. Minimum of the two gives the value of n for each K and we will the return the maximum n.

Below is the implementation of the above approach: 

32629

Time Complexity: O(n) where n is the length of the given string.
Auxiliary Space: O(n)