Sanket & strings

#1

daught- how to approach …
what the question is saying …
can any one explain samle test case…what is happening
any video tutorial on this???

ques-
Sanket has a string consisting of only a and b as the characters. Sanket describes perfectness of a string as the maximum length substring of equal characters. Sanket is given a number K which denotes the maximum number of characters he can change. Find the maximum perfectness he can generate by changing no more than k characters

nput Format:
The first line contains an integer denoting the value of K. The next line contains a string having on ‘a’ and ‘b’ as the characters

Constraints:
2 ≤ N ≤ 10^5

Output Format
Single integer denoting the maximum perfectness achievable

Sample Input
2
abba
Sample Output
4

Need Explanation
#2

@S18LPC-OL0078 Hey rishav according to the question
Sanket has a string consisting of only a and b as the characters. Sanket describes perfectness of a string as the maximum length substring of equal characters. Sanket is given a number K which denotes the maximum number of characters he can change. Find the maximum perfectness he can generate by swapping no more than k characters.

Basically, there is a string which consists of only a and b. A substring is a contiguous sequence of characters within a string. Our aim is to generate substrings of a and b by swapping characters such that the lengths of substrings of either a or b is maximum possible. The only constraint we have here is that only k swaps are allowed. So, you have to tell the maximum possible length of the substrings that can be generated. By swapping, we mean that a can be replaced by b and b can be replaced by a.

For example:
Consider the following string: abba and k = 2
So, we can make only two swaps

abba (swaps = 0)
aaba (swaps = 1)
aaaa (swaps = 2)

Thus, the maximum length of substring is 4.

Consider the string: ababab and k=2

ababab (swaps = 0)
aaabab (swaps =1)
aaaaab (swaps = 2)

Thus, the maximum length of substring is 5.

#3

How to approach in this problem?