Problem Statement

Given is a string $S$ of length $N$ consisting of lowercase English letters. Snuke can do this operation any number of times: remove fox occurring as a substring from $s$ and concatenate the remaining parts of $s$.

What is the minimum possible length of $s$ after some number of operations by Snuke?

Constraints

• $1 \\leq N \\leq 2 \\times 10^{5}$
• $s$ is a string of length $N$ consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

$N$ $s$

Print

Print the minimum possible length of $s$ after some number of operations by Snuke.

Sample Input 1

6
icefox

Sample Output 1

3

• By removing the fox at the end of icefox, we can turn $s$ into ice.

Sample Input 2

7
firebox

Sample Output 2

7

• fox does not occur as a substring.

Sample Input 3

48
ffoxoxuvgjyzmehmopfohrupffoxoxfofofoxffoxoxejffo

Sample Output 3

27