fn main() {
    let mut temp = String::new();
    std::io::stdin().read_line(&mut temp).ok();
    let s = temp.trim().chars().collect::<Vec<_>>();

    let n = s.len();
    for i in 0..n {
        if i == n-1 || s[i] != s[i+1] {
            print!("{}", s[i]);
        }
    }
    println!("");
}