// yukicoder My Practice
// author: Leonardone @ NEETSDKASU

fn main() {
    
    let mut stdin = String::new();
    {
        use std::io::Read;
        std::io::stdin().read_to_string(&mut stdin).expect("failed to read string");    
    }
    let mut stdin = stdin.split_whitespace();
    
    macro_rules! get {
        () => ( stdin.next().unwrap().parse().unwrap() );
        ($t:ty) => ( stdin.next().unwrap().parse::<$t>().unwrap() );
    }
    
    let n: u32 = get!();
      
    for _ in 0..n {
        print!("{}", get!(String));
    }
    
    println!();
}