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 Rust (1.15.1) (judge verdict: Accepted)

use std::io::Read;

fn main() {
    let mut buf = String::new();
    std::io::stdin().read_to_string(&mut buf).unwrap();

    let answer = solve(&buf);

    println!("{}", answer);
}

fn solve(input: &str) -> String {
    let mut iterator = input.split_whitespace();

    let n: usize = iterator.next().unwrap().parse().unwrap();
    let s = iterator.next().unwrap();

    let mut chars = s.chars();
    let mut prev = chars.next().unwrap();
    let mut ans: usize = 1;

    for _i in 1..n {
        let current = chars.next().unwrap();
        if prev != current {
            prev = current;
            ans += 1;
        }
    }

    return format!("{}", ans);
}

#[test]
fn test() {
    assert_eq!(
        solve(
            r"10
aabbbbaaca"
        ),
        "5"
    );
    assert_eq!(
        solve(
            r"5
aaaaa"
        ),
        "1"
    );
    assert_eq!(
        solve(
            r"20
xxzaffeeeeddfkkkkllq"
        ),
        "10"
    );
}