Problem:
Score : 300 points

Problem Statement

There are N slimes lining up from left to right. The colors of these slimes will be given as a string S of length N consisting of lowercase English letters. The i-th slime from the left has the color that corresponds to the i-th character of S.

Adjacent slimes with the same color will fuse into one larger slime without changing the color. If there were a slime adjacent to this group of slimes before fusion, that slime is now adjacent to the new larger slime.

Ultimately, how many slimes will be there?

Constraints

1 \leq N \leq 10^5

|S| = N

S consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

N
S

Output

Print the final number of slimes.

Sample Input 1

10
aabbbbaaca

Sample Output 1

5

Ultimately, these slimes will fuse into abaca.

Sample Input 2

5
aaaaa

Sample Output 2

1

All the slimes will fuse into one.

Sample Input 3

20
xxzaffeeeeddfkkkkllq

Sample Output 3

10

Solution in Ruby (2.3.3) (judge verdict: Wrong Answer)

N = gets.to_i
S = gets.split("")
index = 0

N.times do
    if S[index+2].nil?
        if S[index+1].nil?
            break
        else
            if S[index] == S[index+1] && S[index+1] == S[index+2]
                S.delete_at(index+1)
            elsif S[index] == S[index+1]
                S.delete_at(index+1)
                index += 1
            else
                index += 1
            end
        end
    else
        if S[index] == S[index+1] && S[index+1] == S[index+2]
            S.delete_at(index+1)
        elsif S[index] == S[index+1]
            S.delete_at(index+1)
            index += 1
        else
            index += 1
        end
    end
end

puts S.length