Problem:
Score : 200 points

Problem Statement

In Japan, people make offerings called hina arare, colorful crackers, on March 3.

We have a bag that contains N hina arare. (From here, we call them arare.)

It is known that the bag either contains arare in three colors: pink, white and green, or contains arare in four colors: pink, white, green and yellow.

We have taken out the arare in the bag one by one, and the color of the i-th arare was S_i, where colors are represented as follows - pink: P, white: W, green: G, yellow: Y.

If the number of colors of the arare in the bag was three, print Three; if the number of colors was four, print Four.

Constraints

1 \leq N \leq 100

S_i is P, W, G or Y.

There always exist i, j and k such that S_i=P, S_j=W and S_k=G.

Input

Input is given from Standard Input in the following format:

N
S_1 S_2 ... S_N

Output

If the number of colors of the arare in the bag was three, print Three; if the number of colors was four, print Four.

Sample Input 1

6
G W Y P Y W

Sample Output 1

Four

The bag contained arare in four colors, so you should print Four.

Sample Input 2

9
G W W G P W P G G

Sample Output 2

Three

The bag contained arare in three colors, so you should print Three.

Sample Input 3

8
P Y W G Y W Y Y

Sample Output 3

Four

Solution in Rust (1.15.1) (judge verdict: Accepted)

#![allow(unused_imports, unused_macros, dead_code)]

macro_rules! min {
    (.. $x:expr) => {{
        let mut it = $x.iter();
        it.next().map(|z| it.fold(z, |x, y| min!(x, y)))
    }};
    ($x:expr) => ($x);
    ($x:expr, $($ys:expr),*) => {{
        let t = min!($($ys),*);
        if $x < t { $x } else { t }
    }}
}
macro_rules! max {
    (.. $x:expr) => {{
        let mut it = $x.iter();
        it.next().map(|z| it.fold(z, |x, y| max!(x, y)))
    }};
    ($x:expr) => ($x);
    ($x:expr, $($ys:expr),*) => {{
        let t = max!($($ys),*);
        if $x > t { $x } else { t }
    }}
}
macro_rules! ewriteln {
    ($($args:expr),*) => { let _ = writeln!(&mut std::io::stderr(), $($args),*); };
}
macro_rules! trace {
    ($x:expr) => { ewriteln!(">>> {} = {:?}", stringify!($x), $x) };
    ($($xs:expr),*) => { trace!(($($xs),*)) }
}
macro_rules! put {
    (.. $x:expr) => {{
        let mut it = $x.iter();
        if let Some(x) = it.next() { print!("{}", x); }
        for x in it { print!(" {}", x); }
        println!("");
    }};
    ($x:expr) => { println!("{}", $x) };
    ($x:expr, $($xs:expr),*) => { print!("{} ", $x); put!($($xs),*) }
}

const M: i64 = 1_000_000_007;

fn main() {
    let mut sc = Scanner::new();
    let n: usize = sc.cin();
    let s: std::collections::HashSet<String> = sc.vec::<String>(n).iter().map(|x| x.clone()).collect();
    put!(if s.len() == 4 {
        "Four"
    } else {
        "Three"
    });
}

use std::io::{self, Write};
use std::str::FromStr;
use std::collections::VecDeque;

struct Scanner { stdin: io::Stdin, buffer: VecDeque<String>, }
impl Scanner {
    fn new() -> Self { Scanner { stdin: io::stdin(), buffer: VecDeque::new() } }
    fn cin<T: FromStr>(&mut self) -> T {
        while self.buffer.len() == 0 {
            let mut line = String::new();
            let _ = self.stdin.read_line(&mut line);
            for w in line.split_whitespace() {
                self.buffer.push_back(String::from(w));
            }
        }
        self.buffer.pop_front().unwrap().parse::<T>().ok().unwrap()
    }
    fn chars(&mut self) -> Vec<char> { self.cin::<String>().chars().collect() }
    fn vec<T: FromStr>(&mut self, n: usize) -> Vec<T> { (0..n).map(|_| self.cin()).collect() }
}