'use strict'

const main = input => {
	const s = input.trim().split('\n')[1].split(' ')
	let cnt = 0

	for (let i = 0; i < s.length; i++) {
		if (s[i] === 'Y') cnt++
	}

	if (cnt > 0) console.log('Four')
	else console.log('Three')
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'))
