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 PyPy3 (2.4.0) (judge verdict: Wrong Answer)

import re
n = int(input())
s = input()
memo = ""
isSequenced = False
count = 1
ans = s

for i in s:
  if i != memo and isSequenced == False:
    memo = i
  elif i == memo:
    isSequenced = True
    count += 1
  elif i != memo and isSequenced == True:
    # print("memo is " + memo)
    # print("count is " + str(count))
    # print(memo*count)
    ans = re.sub(memo*count,memo,ans)
    #ans = ans.replace(memo*count,memo)
    memo = i
    isSequenced = False
    count = 1
  # elif i == s[n-1] and isSequenced == True:
  #   print(s[n-1])
  #   ans = re.sub(memo*count,memo,ans)
#print(ans)
if isSequenced == True:
  ans = re.sub(memo*count,memo,ans)
print(len(ans))