'use strict'

const main = input => {
	const args = input.trim().split(' ')
	if (args[0] === 'H' && args[1] === 'H') console.log('H')
	else if (args[0] === 'H' && args[1] === 'D') console.log('D')
	else if (args[0] === 'D' && args[1] === 'H') console.log('D')
	else console.log('H')
}

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